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document number: mma81xxeg rev 5, 04/2010 freescale semiconductor technical data ? freescale semiconductor, inc., 2009, 2010. all rights reserved. digital x-axis or z-axis accelerometer the mma81xxeg (z-axis) and mma82xxeg/mma82xxteg (x-axis) are members of freescale?s family of dsi 2.0-compatible accelerometers. these devices incorporate digital signal pr ocessing for filtering, trim and data formatting. features ? available in 20g, 40g, 150g, and 250g (mma82xxeg, x-axis), 50g and 100g (mma82xxteg, x-ax is) and 40g, 100g, 150g, and 250g (mma81xxeg, z-axis). additional g-ranges may be available upon request ? 80 customer-accessible otp bits ? 10-bit digital data output from 8 to 10 bit dsi output ? 6.3 to 30 v supply voltage ? on-chip voltage regulator ? internal self-test ? minimal external component requirements ? rohs compliant (-40 to +125oc) 16-pin soic package ? automotive aec-q100 qualified ? dsi 2.0 compliant ? z-axis transducer is overdamped typical applications ? crash detection (airbag) ? impact and vibration monitoring ? shock detection. mma81xxeg mma82xxeg mma82xxteg series single-axis dsi 2.0 accelerometer eg suffix (pb-free) 16-lead soic case 475-01 pin connections 116 215 314 413 512 611 710 89 n/c v ss n/c v ss c reg busrtn v pp /test h cap c fil d out v gnd /d in clk busin busout v ss c reg 16-pin soic package
mma81xxeg sensors 2 freescale semiconductor section 1 general description mma81xxeg/mma82xxeg/mma82xxteg family is a satellite accelerometer which is comp rised of a single axis, variable ca- pacitance sensing element with a single channel interface ic. the interface ic converts the analog signal to a digital format w hich is transmitted in accordance with the dsi-2.0 specification. 1.1 overview signal conditioning begins with a capacitance to voltage conversion (c to v) followed by a 2-stage switched capacitor amplifier . this amplifier has adjustable offset and gain trimming and is followed by a low-pass switched ca pacitor filter with bessel func tion. offset and gain of the interface ic are trimmed during the manufacturing process. fo llowing the filter the signal passes to the output stage. the output sta ge sensitivity incorporates temperature compensation. the output of the accelerometer signal cond itioning is converted to a digital signal by an a/d converter. after this conversion the resultant digital word is converted to a serial data stream which may be transmitted via the dsi bus. power for the device is derived from voltage applied to the busin/busout and v ss pins. bus voltage is rectified and applied to an external capacitor connected to the h cap pin. during data transmissions, the device operates from stored charge on the external capacitor. an integrated regulator supplies fixed voltage to internal circuitry. a self-test voltage may be applied to the electrostatic deflection plate in the sensing element. self-test voltage is factory t rimmed. other support circuits include a bandgap voltage refer ence for the bias sources and the self-test voltage. a total of 128 bits of one-time programmable (otp) memory, are provided for storage of factory trim data, serial number and device characteristics. eighty otp bits are available for customer programming. these eighty otp bits may be programmed via the dsi bus or through the serial test/trim interface. otp integr ity is verified through continuous parity checking. separate p arity bits are provided for factory and customer pr ogrammed data. in the event that a parity fault is detected, the reserved value of zero is transmitted in response to a read acceleration data command. a block diagram illustrating the major elements of the device is shown in figure 1-1 . ordering information device name x-axis g-level z-axis g-level temperature range soic 16 package packaging mma8225egr2 250 ? -40 to +125c 475-01 tape & reel mma8225eg 250 ? -40 to +125c 475-01 tubes mma8215egr2 150 ? -40 to +125c 475-01 tape & reel mma8215eg 150 ? -40 to +125c 475-01 tubes mma8210tegr2 100 ? -40 to +125c 475-01 tape & reel mma8210teg 100 ? -40 to +125c 475-01 tubes mma8205tegr2 50 ? -40 to +125c 475-01 tape & reel mma8205teg 50 ? -40 to +125c 475-01 tubes mma8204egr2 40 ? -40 to +125c 475-01 tape & reel mma8204eg 40 ? -40 to +125c 475-01 tubes mma8202egr2 20 ? -40 to +125c 475-01 tape & reel mma8202eg 20 ? -40 to +125c 475-01 tubes mma8125egr2 ? 250 -40 to +125c 475-01 tape & reel mma8125eg ? 250 -40 to +125c 475-01 tubes mma8115egr2 ? 150 -40 to +125c 475-01 tape & reel mma8115eg ? 150 -40 to +125c 475-01 tubes mma8110egr2 ? 100 -40 to +125c 475-01 tape & reel mma8110eg ? 100 -40 to +125c 475-01 tubes mma8104egr2 ? 40 -40 to +125c 475-01 tape & reel mma8104eg ? 40 -40 to +125c 475-01 tubes
mma81xxeg sensors freescale semiconductor 3 figure 1-1. overall block diagram busout busin busrtn logic command decode state machine response generation bandgap reference oscillator g-cell c-to-v converter low-pass filter offset trim gain trim tcs trim selftest trim osc trim selftest voltage self-test enable voltage regulator c reg h cap internal supply voltage otp programming interface v pp /test d out clk c fil v ss c reg v ss n/c a-to-d converter regulator trim 16 15 14 11 12 9 8 6 5 4 3 13 1 v ss 10 n/c 2 v gnd /d in ground loss detector 7 switches shown in normal operating configuration
mma81xxeg sensors 4 freescale semiconductor 1.2 package pinout the pinout for this 16-pin device is shown in figure 1-2 . figure 1-2. device pinout 116 215 314 413 512 611 710 89 n/c v ss n/c v ss c reg busrtn v pp /test h cap c fil d out v gnd /d in clk busin busout v ss c reg 16-pin soic package activiation of x-axis self-test -x causes output to become more positive +z -z n/c: no internal connection +1 g -1 g 0 g 0 g +1 g -1 g 0 g 0 g +x output response to displacement in the direction of arrows. response to static orientation within 1 g field. to center of gravitational field projection activation of z-axis self-test causes output to become more positive case: 475-01
mma81xxeg sensors freescale semiconductor 5 1.3 pin functions the following paragraphs provide descripti ons of the general function of each pin. 1.3.1 h cap and v ss power is supplied to the asic through busin or busout and busrtn. the supply voltage is rectified internally and applied to the h cap pin. an external capacitor connected to hcap forms the positive supply for the integrated voltage regulator. v ss is supply return node. all v ss pins are internally connected to busrtn . to obtain specified performance, all v ss nodes should be connected to the busrtn node on the pwb. to ensure stability of the internal voltage regulat or and meet dfmea requirements, the connection from h cap to the external capacitor should be as short as possible and should not be routed elsewhere on the printed wiring assembly. the voltage on h cap is monitored. if the voltage falls be low a specified level, the device will return the value zero in response to a short word read acceleration data command, and report th e undervoltage condition by setting the undervoltage (u) flag. should the undervoltage condition persist for more than one millis econd, the internal power-on reset (por) circuit is activated and the device will not respond until the voltage at h cap is restored to operating levels and the device has undergone post-reset initialization. 1.3.2 busin the busin pin is normally connected to the dsi bus and supports bidirectional commun ication with the master. the mma81xxeg, mma82xxeg and mma82xxteg supp orts reverse initialization for improv ed system fault to lerance. in the event that the dsi bus cannot support communication between the master and busin pin, commun ication with the master may be conducted via the busout pin and the busin pi n can be used to access other dsi devices. 1.3.3 busout the busout pin is normally connected to the dsi bus for daisy-cha ined bus configurations. in supp ort of fault tolerance at the system level, the busout pi n can be used as an input for reverse initialization and data communication. the internal bus switch is always open following reset. the bus swit ch is closed when data bit d6 is set when an initialization or reverse initialization command is received. 1.3.4 busrtn this pin provides the common return for power and signalling. 1.3.5 c reg the internal voltage regulator requires external capacitance to the v ss pin for stability. this should be a high grade capacitor without excessive internal resistance or inductance. an optional electrolytic capacitor may be required if a longer power down delay is required. figure 1-3 illustrates the relationship between capacitance, se ries resistance and voltage regulator stability. two c reg pins are provided for redundancy. it is recommended that both c reg pins are connected to the exte rnal capacitor(s) for best system reliability. figure 1-3. voltage regulator capacitance and series resistance c reg 1 f100 f unstable esr stable stable, unacceptable 0 700 m noise performance
mma81xxeg sensors 6 freescale semiconductor 1.3.6 c fil the output of the sensor interface circuitry can be monitored at the c fil pin. an internal buffer is provided to provide isolation between external signals and the input to the a/d converter. if c fil monitoring is desired, a low-pa ss filter and a buffer with high input impedance located as close to this pin as possi ble are required. the circuit configuration shown in figure 1-5 is recommended. figure 1-4. c fil filter and buffer configuration this pin may be configured as an input to the a/d conv erter when the mma81xxeg, mm a82xxeg and mma82xxteg devices are in test mode. refer to appendix a for further details regarding test mode operation. 1.3.7 trim/test pins (v pp /test, clk, dout) these pins are used for programming the device during manufactur ing. these pins have internal pull-up or pull-down devices to drive the input when left unconnected. the following terminat ion is recommended for these pins in the end application: clk may be connected to ground, however this is not advised if th e glde bit in devcfg2 is set, as a short between the adjacent v gnd /d in pin and ground prevents ground loss detection. 1.3.8 gnd detect pin (v gnd /d in ) v gnd /d in may be used to detect an open condition between the satellit e module and chassis. the ground loss detector circuit supplies a constant current through v gnd /d in and measures resulting voltage. this determines the resistance between v gnd / d in and the system?s virtual ground. a fault co ndition is signalled if the resistance exceeds specified limits. this pin has no in ternal pull-down device and must be connected as shown in figure 1-5 . ground loss detection circuitry is enabled when the glde bit is programmed to a logic ?1? state in devcfg2. ground loss detection is not available when the master operates in differential mode. v gnd /d in must be directly connected to busrtn if the dsi bus is configured for differential operation. v gnd /d in connection options are illustrated in figure 1-5 . when ground loss detection is enabled, a c onstant current is sourced and the voltage at v gnd is continuously monitored. an open connection between v ss and chassis ground will cause the voltage to rise. if the voltage indicates that the connection between chassis ground and v ss has opened, a 14-bit counter is enabled. this co unter will reverse if the voltage falls below the detection threshold. should the counter overflow, a ground loss co ndition is indicated. the counter acts as a digital low-pass filter, to provide immunity from spurious signals. this pin functions as the spi data input when the device is in test mode. table 1-1 pin termination v pp /test connect to ground clk leave unconnected d out leave unconnected 680 pf 50 k 5 mma81xxeg/mma82xxeg//mma82xxteg c fil rin 1 m
mma81xxeg sensors freescale semiconductor 7 figure 1-5. v gnd /d in connection options 1.4 module interconnect a typical satellite module configuration suppo rting daisy-chain configuration is shown in figure 1-6 . capacitors c1 and c2 form a filter network for the internal voltage regulator. two ca pacitors are shown for redundancy; this configuration improves reliability in the event of an open capacitor connection. a single 1 f capacitor may be used in place of c1 and c2, however connection from the capacitor to both creg pins is requ ired. chold stores energy duri ng signal transitions on busin and busout. the value of this capacitor is typically 1 f; however, this depends upon data rates and bus utilization. figure 1-6. typical satellite module diagram 1.5 device identification thirty-two otp bits are factory-programmed with a unique serial number during the manufacturing and test. five additional bits are factory-programmed to indicate the fu ll-scale range and axis of sensitivity. device identification data may be read at any time while the device is active. busrtn 1 nf chassis 1.00 k , 1% 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 mma81xxeg/mma82xxeg/mma82xxteg n/c v ss n/c v ss c reg busrtn v pp /test busin c fil d out v gnd /d in clk busout h cap v ss c reg busrtn ground-loss detection disabled g round-loss detection enabled (single-ended systems only) 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 mma81xxeg/mma82xxeg/mma82xxteg n/c v ss n/c v ss c reg busrtn v pp /test busin c fil d out v gnd /d in clk busout h cap v ss c reg busrtn c hold busout c1 1 f c2 1 f n/c busin see note 16 15 14 13 12 11 10 9 1 2 3 4 5 6 7 8 mma81xxeg/mma82 xxeg/mma82xxteg n/c v ss n/c v ss c reg busrtn v pp /test busin c fil d out v gnd /d in clk busout h cap v ss c reg note: leave open or connect to signal monitor.
mma81xxeg sensors 8 freescale semiconductor section 2 su pport modules 2.1 master oscillator a temperature-compensated internal oscillator provides a stabl e timing reference for the device. the oscillator is factory-trim med to operate at a nominal frequency of 4 mhz. 2.2 voltage regulation the internal voltage regulator has minimum voltage level dete ction, which will hold the device in reset and prevent data transmission should the regulator output fall during operation. the regulator also has an input voltage clamp to limit the powe r dissipated in the regulator during voltage spikes on the h cap pin which might come from the two or three wire satellite bus. 2.3 bessel filter 180-hz, 2-pole and 400 hz 4-pole bessel filter options are pr ovided. the low-pass filter is implemented within a two stage switched capacitor amplifier. the overall gain of the bessel filt er is set to a fixed value. the output of the bessel filter ou tput acts as the input to the a/d converter and is also buffered and made available at the c fil pin. 2.4 status monitoring a number of abnormal conditions are detected by mma81 xxeg/mma82xxeg/mma82xxteg and t he behavior of the device altered if a fault is det ected. detected fault conditions and consequent dev ice behavior is summarized in the table below. cert ain conditions, e.g. ground loss, are qu alified by device configuration. figure 2-1 provides a representation of fault conditions, appli- cable qualifiers and effects. table 2-1 fault condition response summary condition description device behavior undervoltage, c reg internally regulated voltage below operating level device continuously undergoes reset, bus switch open, no response to dsi commands sustained undervoltage, h cap voltage at hcap below operating level for more than 1 ms frame timeout bus voltage remains below frame threshold (t to ) longer than specified time. transient undervoltage, h cap voltage at hcap below operating level for less than 1 ms undervoltage (u) flag set, short-word read acceleration data response value equals zero fuse fault otp fuse threshold failure accelerometer status (s) flag set, short-word read acceleration data response value equals zero parity fault parity failure detected in factory or customer programmed otp data ground fault ground loss detected for more than 4.096 ms accelerometer status (s) and ground fault (gf) flags set, short-word read acceleration data response value equals zero
mma81xxeg sensors freescale semiconductor 9 figure 2-1. status logic representation the signal stdis in figure 2-1 is set when self-test lockout is activated throu gh the execution of two consecutive disable self- test stimulus commands, as described in section 4.6.6 . if self-test lockout has been activa ted, a dsi clear command or power- on reset is required to clear a fault condition which results in reset of the d flip-flop. ddis fuse error gf glde lock1 par1 fault lock2 par2 fault d r q st 1 s transient undervoltage condition short word acceleration data = 0 key: ddis device disable bit, devcfg2[4] fuse fault otp fuse threshold failure glde ground loss detection bit, devcfg2[5] gf ground fault detection condition lock1 factory programmed otp lock bit lock2 customer programmed otp lock bit par1 fault factory programmed otp parity fault condition s accelerometer status flag st self-test activation condition par2 fault customer programmed otp parity fault condition u stdis self-test disable stdis u undervoltage flag
mma81xxeg sensors 10 freescale semiconductor section 3 otp memory mma81xxeg/mma82xxeg/mma82xxteg family fe atures one-time-programmable (otp ) memory implemented via a fuse array. otp is organized as an array of 96 bits which contains the trim data, configuration data , and serial number for each dev ice. sixteen bits of the otp array may be progra mmed by the customer through the dsi bus. 3.1 internal register array and otp memory contents of otp memory are transferred to a set of registers following power-on reset, after which the otp array is powered- down. contents of the register array are static and may be read at any time following the transfer of data from the otp memory. write operations to otp mirror registers are supported when the device is in test mode, however any data stored in the register will be lost when the device is powered down. the mirror regist ers are also restored when an otp read operation is performed. in addition to the registers which mirror otp memory contents, several other registers are provided. among these are the otp control registers which controls otp programming operations an d may be used to restore the registers from the otp memory. figure 3-1. otp interface overview 3.2 otp word assignment customer-accessible otp bits are shown in table 3-1 . unprogrammed otp bits are read as logic ?0? values. devcfg1, devcfg2 and registers reg-8 through reg- f are programmed by the customer. other bits are programmed and locked during manufacturing. there is no requirement to program any bits in devcfg1 or devcfg2 for the device to be fully operational. table 3-1 customer accessible data location bit function addressregister76543210 $00 sn0 s7s6s5s4s3s2s1 s0 $01 sn1 s15 s14 s13 s12 s11 s10 s9 s8 $02 sn2 s23 s22 s21 s20 s19 s18 s17 s16 $03 sn3 s31 s30 s29 s28 s27 s26 s25 s24 $04 type order 0 axis 0 0 rng2 rng1 rng0 $05 reserved 0 000000 0 $06 devcfg1 customer defined at1 at0 $07 devcfg2 lock2 par2 glde ddis ad3 ad2 ad1 ad0 $08 reg-8 customer defined $09 reg-9 customer defined $0a reg-a customer defined $0b reg-b customer defined $0c reg-c customer defined $0d reg-d customer defined $0e reg-e customer defined $0f reg-f customer defined clk d out d in v pp /test serial peripheral interface register array otp array to digital interface
mma81xxeg sensors freescale semiconductor 11 3.2.1 device serial number a unique serial number is programmed into each device during ma nufacturing. the serial number is composed of the following information. lot numbers begin at 1 for all devices produced and are sequentially assigned. serial numbers begin at 1 for each lot, and are sequentially assigned. no lot will contain more devices than c an be uniquely identified by the 13-bit serial number. not all al low- able lot numbers and serial numbers will be assigned. 3.2.2 type byte the type byte is programmed at final trim and test to indicate the axis of orientation of th e g-cell and the calibrated range o f the device. 3.2.2.1 filter characteristic bit (order) this bit denotes the low-pass filter characteristic. 0 - 400 hz, 4-pole 1 - 180 hz, 2-pole 3.2.2.2 bit 6 bit 6 is reserved. it will always be read as a logic ?0? value. 3.2.2.3 axis of sensitivity bit (axis) the axis bit indicates direction of sensitivity 0 - z-axis 1 - x-axis 3.2.2.4 bit 4, bit 3 bit 4 and bit 3 are reserved. they will always be read as a logic ?0? value. 3.2.2.5 full-scale range bits (rng2 - rng0) these three bits define the calibrated range of the device as follows: table 3-2 serial number assignment bit range content s12 - s0 serial number s31 - s13 lot number table 3-3 device type register location bit function addressregister76543210 $04 type order 0 axis 0 0 rng2 rng1 rng0 table 3-4 rng2 rng1 rng0 range 0 0 0 unused 0 0 1 20g 0 1 0 40g 0 1 1 50g 1 0 0 100g 1 0 1 150g 1 1 0 250g 1 1 1 unused
mma81xxeg sensors 12 freescale semiconductor 3.2.3 configuration bytes two customer-programmable configuration bytes are assigned. 3.2.4 device configuration byte 1 (devcfg1) configuration byte 1 contains three defined bit functions, plus fi ve bits that can be programmed by the customer to designate a ny coding desired for packaging axis, model, etc. 3.2.5 attribute bits (at1, at0) these bits may be assigned by the customer as desired. they are transmitted by mma81xxeg/mma82xxeg/mma82xxteg in response to request status, disable self-test stimulus or enable self-test stimulus commands, as described in section 4 . 3.2.6 device configuration byte 2 (devcfg2) configuration byte 2 contains six bits t hat can be programmed by the customer to c ontrol device configurat ion, along with parit y and lock bits for devcfg1 and devcfg2. 3.2.6.1 customer data lock bit (lock2) the bits in configuration bytes 1 and 2 are frozen when the lock2 bit is programmed. the lock2 bit is not included in the parit y check. locking does not take effect after this bit is programmed until the device has been subsequently reset. 0 - customer-programmed data area unlocked. 1 - programming operations inhibited. the ddis bit is not affected by lock2 and may be programmed at any time. 3.2.6.2 customer data parity bit (par2) the par2 parity bit is used for detecting changes in conf iguration bytes 1 and 2 along with registers reg-8 through reg-f (addresses $06 through $0f, inclusive). a fault condition is indicat ed if a change to parity-protected register data is detecte d. the par2 bit follows an ?even? parity scheme (number of logical high bits including parity bit is even). if an internal parity error is detected, the device will respond to read acceleration data command s with zero in the data field , as described in section 4.5.4 . the status (s) bit will be set in either short word or long word responses to indicate the fault condition. a parity fault may result from a bit failure within the otp or the registers which store an im age of the otp during operation. in the latter case, power-on reset will clear the fault when the r egisters are re-loaded. a parity fault associated with the otp a rray is a non-recoverable failure. the parity status of customer programmed data is not monitore d if the lock2 bit is not programmed to a logic ?1? state. 3.2.6.3 ground loss detection enable (glde) when this bit is programmed to a logic ?1? value, ground loss errors will be reported if a ground fault condition is detected. 1 - ground-loss detection circuitry enabled 0 - ground-loss detection disabled. table 3-5 device configuration byte 1 location bit function addressregister76543210 $06 devcfg1 customer defined att1 att0 table 3-6 device configuration byte 2 location bit function addressregister76543210 $07 devcfg2 lock2 par2 glde ddis ad3 ad2 ad1 ad0
mma81xxeg sensors freescale semiconductor 13 3.2.6.4 device disable bit (ddis) this bit may be programmed at any time, regardless of the state of lock2. this bit is intended to be programmed when a module has been determined by the dsi bus master to be defective. prog ramming this bit after lock2 has been set will cause the device to respond to short word read acceleration data commands with a zero response. acceleration results are not affected by this bit when long word read acceleration data commands are executed, however the status (s) bit will be set in the response. 1 - device responds to read acceleration data command with zero value 0 - device responds normally to read acceleration data command 3.2.6.5 device address (ad3 - ad0) these bits define the pre-programmed dsi bus device address. 3.3 otp programming two different methods of programming the eighty customer defi ned bits are supported. in te st mode, these may be programmed in the same manner as factory programmed otp bits. additi onally, the read write nvm dsi bus command may be used. test mode programming operations are described in appendix a.3 . read write nvm command operation is described in section 4.6.3 .
mma81xxeg sensors 14 freescale semiconductor section 4 physical layer and protocol mma81xxeg/mma82xxeg/mma82xxteg family is compliant with the dsi bus st andard, version 2.0. mma81xxeg/ mma82xxeg/mma82xxteg is designed to be co mpatible with either dsi version 2 or dsi version 1.1 compliant bus masters. 4.1 dsi network physical layer interface refer to section 3 of the dsi bus standard for information regarding the physi cal layer interface. 4.2 dsi network data link layer refer to section 4 of the dsi bus standard for information regarding the dsi network data link layer interface. both standard and enhanced command structures are supported for short word and long word commands. 4.3 dsi bus commands dsi bus commands which are recognized by mma81x xeg and the mma82xxeg/mma82xxteg are summarized in table 4-1 . detailed descriptions of each supported command are descr ibed in subsequent sections of this document. if a crc error is detected, or a reserved or unimplemented command is received, the device will not respond. following all messages, mma8 1xxeg and the mma82xxeg/mma82xxt eg disregards the dsi bus voltage level for approxi- mately 18.5 s. within this time, all supported commands except init ialization and reverse initialization are guaranteed to be executed and the device will be ready for the next message. when the bus voltage falls below the signal high logic level (see section 5 ) after the 18.5 s period has elapsed, the device will respond as appr opriate to a command sent to it in the previous message. exactly one response is attempted; if a noise spike or corrupted transf er occurs, the response is not retried. if an initialization or reverse in itialization command is execut ed and the bus switch (bs) bi t is set, mma81xxeg, mma82xxeg and mma82xxteg will disregard the bus voltage level for a nominal period of 180 s. this interval allows for the bus voltage to recover following closure of the bus switch, while the hold capacitor of a downstream slave charges. legend: bs: bus switch control (0: open, 1: close) nv: nonvolatile memory control (1: program nvm) pa3 - pa0: device address assigned during initialization or reverse initialization ra3 - ra0: internal user data register address fa2 - fa0: format register address fd3 - fd0: format register data content table 4-1 dsi bus command summary command size data binary hex description c3 c2 c1 c0 d7 d6 d5 d4 d3 d2 d1 d0 0 0 0 0 $0 initialization lw nv bs b1 b0 pa3 pa2 pa1 pa0 0 0 0 1 $1 request status sw ? ? ? ? ? ? ? ? 0 0 1 0 $2 read acceleration data sw ? ? ? ? ? ? ? ? 0 0 1 1 $3 not implemented n/a not applicable 0 1 0 0 $4 request id information sw ? ? ? ? ? ? ? ? 0 1 0 1 $5 not implemented n/a not applicable 0 1 1 0 $6 not implemented n/a not applicable 0 1 1 1 $7 clear sw ? ? ? ? ? ? ? ? 1 0 0 0 $8 not implemented n/a not applicable 1 0 0 1 $9 read write nvm lw ra3 ra2 ra1 ra0 rd3 rd2 rd1 rd0 1 0 1 0 $a format control lw r/w fa2 fa1 fa0 fd3 fd2 fd1 fd0 1 0 1 1 $b read register data lw 0 0 0 0 ra3 ra2 ra1 ra0 1 1 0 0 $c disable self-test stimulus sw ? ? ? ? ? ? ? ? 1 1 0 1 $d activate self-test stimulus sw ? ? ? ? ? ? ? ? 1 1 1 0 $e reserved n/a not applicable 1 1 1 1 $f reverse initialization lw nv bs b1 b0 pa3 pa2 pa1 pa0
mma81xxeg sensors freescale semiconductor 15 4.4 command response summaries the device incorporates an analog-to-digital converter which trans lates the low-pass filtered acceleration signal to a 10-bit b inary value. the 10-bit digital result is referred to as ad9 through ad0 in the response tables which follow. 4.4.1 short word response summary short word responses for a ll commands are summarized below. detailed dsi command descriptions may be found in section 4.5 . legend: at1 - at0: attribute codes (see section 4.5.1.3 ) nv: state of fuse program control bit bs: state of bus switch (0: open, 1: closed) s: accelerometer status flag (1: internal error) st: self-test flag (1: self-test active) u - undervoltage condition v2 - v0: version id table 4-2 short-word response summary command response hex description d7 d6 d5 d4 d3 d2 d1 d0 $0 initialization not applicable $1 request status nv u st bs at1 at0 s gf $2 read acceleration data see section 4.5.4 $3 not implemented no response $4 request id information v2 v1 v0 0 0100 $5 not implemented no response $6 not implemented no response $7 clear no response $8 not implemented no response $9 read/write nvm not valid $a format control not valid $b read register data not valid $c disable self-test stimulus nv u st bs at1 at0 s gf $d activate self-test stimulus nv u st bs at1 at0 s gf $e reserved no response $f reverse initialization not valid
mma81xxeg sensors 16 freescale semiconductor 4.4.2 long word response summary long word responses for all commands are summarized belo w. detailed dsi command descriptions may be found in section 4.5 . legend: a3 - a0: device address ad9 - ad0: 10-bit acceleration data result at1 - at0: attribute codes (see section 4.5.1.3 ) bf: bus fault flag (1: bus fault) bs: state of bus switch (0: open, 1: closed) fa2 - fa0: format register address fd3 - fd0: format register data content gf: ground fault detected nv: state of fuse program control bit pa3 - pa0: device address assigned duri ng initialization/reverse initialization ra3 - ra 0: internal user data register address rd7 - rd0: internal user data register contents r/w: read/write flag for format control register access s: accelerometer status flag (1: internal error) st: self-test flag (1: self-test active) u - undervoltage condition v2 - v0: version id table 4-3 long-word response summary command response hex description d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 $0 initialization a3 a2 a1 a0 0 0 0 bf nv bs b1 b0 pa3 pa2 pa1 pa0 $1 request status a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf $2 read acceleration data a3 a2 a1 a0 gf s ad9 ad8 ad7 ad6 ad5 ad4 ad3 ad2 ad1 ad0 $3 not implemented no response $4 request id information a3 a2 a1 a0 0 0 0 0 v2 v1 v0 0 0 1 0 0 $5 not implemented no response $6 not implemented no response $7 clear no response $8 not implemented no response $9 read/write nvm a3 a2 a1 a0 see section 4.6.3 $a format control a3 a2 a1 a0 0 1 1 0 r/w fa2 fa1 fa0 fd3 fd2 fd1 fd0 $b read register data a3 a2 a1 a0 ra3 ra2 ra1 ra0 rd7 rd6 rd5 rd4 rd3 rd2 rd1 rd0 $c disable self-test stimulus a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf $d activate self-test stimulus a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf $e reserved no response $f reverse initialization a3 a2 a1 a0 0 0 0 bf nv bs b1 b0 pa3 pa2 pa1 pa0
mma81xxeg sensors freescale semiconductor 17 4.5 dsi command detail detailed descriptions of command formats and responses are provided in this section. 4.5.1 dsi command and response bit descriptions the following abbreviations are used in the descriptions of dsi commands and responses. 4.5.1.1 dsi device address - (a3 - a0) dsi device address. this address will be set to the pre-programm ed device address following reset, or zero if no pre-programmed address has been assigned. if zero, the device address may be assigned during initialization or reverse initialization. 4.5.1.2 acceleration data - (ad9 - ad0) ten-bit acceleration result produced by the device. this value is returned by the read acceleration data command, described in section 4.5.4 . 4.5.1.3 attribute code bits (at1, at0) these bits indicate the contents of devcfg1 bits 1 and 0 in res ponse to a request status, activate self-test stimulus or disabl e self-test stimulus command. 4.5.1.4 bank select (b1, b0) these bits are assigned during initialization or reverse initializat ion to select specific fields within the customer accessibl e data registers. bank selection affects read/write nvm command operati on. invalid combinations of b1 and b0 result in no response from the device to the associated initia lization or reverse initialization command. refer to section 4.6.3 for further details regarding regi ster programming and bank selection. 4.5.1.5 bus fault bit (bf) this bit indicates the success or failure of the bus test which is performed as part of an init ialization or reverse initializa tion com- mand. 1 - bus fault detected 0 - bus test passed 4.5.1.6 bus switch control/status bit (bs) this bit controls the state of the bus switch during an initia lization or reverse initialization command. it also indicates the state of the bus switch in response to the initialization, request st atus, disable self-test stimulus, activate self-test stimulus an d reverse initialization commands. 1 - close bus switch, or bus switch closed 0 - leave bus switch open, or bus switch opened 4.5.1.7 format control register address (fa2 - fa0) this three-bit field selects one of eight format contro l registers. format control registers are described in section 4.6.4.3 . 4.5.1.8 format register data (fd3 - fd0) contents of a format control register. this is the data to be wr itten to the register by a forma t control command, or the conte nts read from the register in response to a format control command. table 4-4 attribute code bit assignments lock2 devgfg1[1] devgfg1[0] at1 at0 0 x x 1 0 1 0 0 0 0 0 1 0 1 1 0 1 0 1 1 1 1
mma81xxeg sensors 18 freescale semiconductor 4.5.1.9 ground fault flag (gf) if ground loss detection has been enabled and a ground fault condi tion is detected, this bit will be set in the response to req uest status, read acceleration data, disable self-test stimulus or ac tivate self-test stimulus commands. if ground loss detection is not enabled, this bit will always be read as a logic ?0? value. 1 - ground fault condition detected 0 - ground connection within specified limits, or ground loss detection disabled. 4.5.1.10 nonvolatile memory program control bit (nv) this bit enables programming of customer-programmed otp locations when set during an initialization or reverse initialization command. data to be programmed are transferred to the device during subsequent read write nvm commands. 1 - enable otp programming 0 - otp programming circuitry disabled 4.5.1.11 assigned device address (pa3 - pa0) this field contains the device address to be assigned during an initialization or reverse initialization command. the address assigned is reported by the device in response to the initialization or reverse initialization command. 4.5.1.12 register address (ra3 - ra0) this field determines the register associated with a read write nvm or read register data command. the two bank select bits (b1, b0) are used to additionally specify a nibble or bit when a read write nvm command is executed. 4.5.1.13 register data (rd7 - rd0) rd3 - rd0 contain data to be written to an otp location when a read write nvm command is executed if the nv bit is set. rd3 - rd0 contain the data read from the selected register in respons e to a read write nvm command if the nv bit is cleared. rd7 - rd0 indicate the contents of the selected regist er in response to a read register data command. 4.5.1.14 format control register read/write bit (r/w) this bit controls the operation performed by a format control command. 1 - write format control register selected by fa2 - fa0 0 - read format control register unless global command 4.5.1.15 accelerometer status flag (s) this bit provides a cumulative indication of the vari ous error conditions which are monitored by the device. 1 - either one or more error conditions have been detected an d/or the internal self-test stimulus circuitry is active 0 - no error condition has been detected the following conditions will cause the status flag to be set: *internal self-test stimulus circuitry is active otp array parity fault otp fuse threshold fault (p artially-programmed fuse) transient undervoltage condition ground fault (if glde bit in devcfg2 is set) 4.5.1.16 self-test state (st) this bit indicates whether internal self-tes t stimulus circuitry is acti ve in response to request status, disable self-test sti mulus and activate self-test stimulus commands. 1 - self-test stimulus active 0 - self-test stimulus disabled 4.5.1.17 undervoltage flag (u) this flag is set if the voltage at hcap is below a specified threshold. refer to section 1.3.1 and section 5 for further details.
mma81xxeg sensors freescale semiconductor 19 4.5.2 initialization command the initialization command conforms to the description provided in section 6.2.1 of the dsi bus standard, version 2.0. at power- up the device is fully compliant with the dsi 1.1 protocol. the initialization command must be transmitted as a dsi 1.1 complia nt long command structure. f eatures of the dsi 2.0 pr otocol can not be accessed until a vali d dsi 1.1 compliant initialization sequence is performed and the enhanced mode format registers are properly configured. figure 4-1 illustrates the sequence of operatio ns performed following negation of inter nal power-on reset (por) and execution of a dsi initialization command. initializ ation commands are recognized only at bu sin. the busout node is tested for a bus short to battery high voltage condition, a nd the bus fault (bf) flag set if an error condition is detected. if no bus fault con dition is detected and the bs bit is set in the command structure, the bus switch will be closed. if the bs bit is set, the dsi bus volta ge level is disregarded for approximately 180 s following initialization to allow the hold capacitor on a downstream slave to charge. if the device has been pre-programmed, pa3 - pa0 and a3 - a0 must match the pre-programmed address. if no device address has been previously programmed into the otp array, pa3 - pa0 c ontain the device address, while a3 - a0 must be zero. if any addressing condition is not met, the device address is not assi gned, the bus switch will remain open and the device will not respond to the initialization command. in the response, bits d15 - d12 and d3 - d0 will contain the device address. if the dev ice was unprogrammed when the initialization command was issued, the device address is assigned as the command executes. both fields will contain the value pa3 - pa0 to indicate successf ul device address assignment. initialization or reverse initialization commands which attempt to assign device address zero are ignored. table 4-5 initialization command structure data address command crc d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 c3 c2 c1 c0 nv bs b1 b0 pa3 pa2 pa1 pa0 a3 a2 a1 a0 0 0 0 0 4 bits table 4-6 initialization command response data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 bf nv bs b1 b0 a3 a2 a1 a0 4 bits
mma81xxeg sensors 20 freescale semiconductor figure 4-1. initialization sequence por initialization command at load registers from fuse array negated close bus switch measure busout voltage enable i resp current drive at busout v busout < v thh ? busin? bs == 1? wait for next dsi bus command close bus switch measure busin voltage enable i resp current drive at busin v busin < v thh ? bs == 1? y n y n y n y n y n y n set bf flag set bf flag reverse initialization command at busout? delay 10 s delay 10 s
mma81xxeg sensors freescale semiconductor 21 4.5.3 request status command the request status command may be transmitted as either a ds i long command structure or a dsi short command structure of any length. the data field in the command structure is ignored but is included in the crc calculati on. no action is taken if th is command is sent to the dsi global device address. 4.5.4 read acceleration data command the read acceleration data command may be transmitted as either a dsi long command structure or a dsi short command structure of any length. the data field in the command structure is ignored but is in cluded in the crc calculation. no action i s taken if this command is sent to the dsi global device address. table 4-1 request status command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3 a2 a1 a0 0 0 0 1 0 to 8 bits table 4-2 short response structure - request status command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 8 nv u st bs at1 at0 s gf 9 0 10 0 11 0 12 0 13 0 14 0 15 0 table 4-3 long response structure - request status command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf 0 to 8 bits table 4-4 read acceleratio n data command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3 a2 a1 a0 0 0 1 0 0 to 8 bits table 4-5 short response structure - read acceleration data command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 8 ad9 ad8 ad7 ad6 ad5 ad4 ad3 ad2 9 ad9 ad8 ad7 ad6 ad5 ad4 ad3 ad2 ad1
mma81xxeg sensors 22 freescale semiconductor data returned in response to a read acceleration data command varies, as illustrated in table 4-5 and table 4-6 . the result is also affected by the state of the self-t est circuitry and internal parity. if the self-test circuitry is enabled, the st bit wi ll be set in data bit d12 of a short word response. if a transient undervoltage condition, parity fault, ground fault or device disable cond ition exists, the reserved data value of zero will be reported in respons e to a short word command structure to indicate that a fault condition has been detected. the data value is not affected by a fault condition when a long word response is reported, however the s and gf bits will be set as appropriate. if the self-test circuitry is active, acceleration data is repo rted regardless of parity faults. the status (s) bit will be set in either short word or long word responses if a parity fault is detected. 4.5.4.1 acceleration data representation acceleration values may be determined from the 10-bit digital output (dv) as follows: a = sensitivity (dv - 512) sensitivity is determined by nominal full-scale range (fsr), lin ear range of digital values and a scaling factor to compensate for sensitivity error. the linear range of digital values for mma81xxeg/mma82xxeg/mma 82xxteg is 1 to 1023. the digital value of 0 is reserved as an error indicator. for the linear ranges of digital values indicated, the nominal value of 1 lsb for each full-scale range is shown in the table b elow. 10 ad9 ad8 ad7 ad6 ad5 ad4 ad3 ad2 ad1 ad0 11 s 12 gf 13 st 14 devcfg1[0] 15 devcfg1[1] table 4-6 long response structure - read acceleration data command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 gf s ad9 ad8 ad7 ad6 ad5 ad4 ad3 ad2 ad1 ad0 0 to 8 bits table 4-7 nominal sensitivity (10-bit data) full-scale range (g) nominal sensitivity (g/digit) 250 0.61 150 0.366 100 0.244 50 0.122 40 0.0976 20 0.0488 table 4-5 short response structure - read acceleration data command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0
mma81xxeg sensors freescale semiconductor 23 4.6 acceleration measurement timing upon verification of the c rc associated with a read a cceleration data command, mma81xxeg/mma82xxeg/mma82xxteg initiates an analog-to-digital conversion. the conversion occurs during the inter frame separation (ifs) and involves a delay during which the busin line is allowed to stabilize, a sample period and finally the translation of the analog signal level to a digital result. 4.6.1 request id information command the request id information command may be transmitted as eit her a dsi long command structure or a dsi short command structure of any length. the data field in the command structure is ignored but is in cluded in the crc calculation. no action i s taken by mma81xxeg/mma82xxeg/mma82xxteg if this command is sent to the dsi global device address. 4.6.2 clear command the clear command may be transmitted as either a dsi long comm and structure or a dsi short command structure of any length. the data field in the command structure is ignored but is included in the crc calculation. when a clear command is successfully decoded and the addre ss field matches either the assigned device address or the dsi global device address, the bus switch is opened and the device undergoes a full reset operation. there is no response to the clear command. table 4-8 request id information command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3 a2 a1 a0 0 1 0 0 0 to 8 bits table 4-9 short response structure - request id information command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 8 v2 v1 v0 0 0 1 0 0 9 0 10 0 11 0 12 0 13 0 14 0 15 0 table 4-10 long response structure - request id information command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 0 v2 v1 v0 0 0 1 0 0 0 to 8 bits table 4-11 clear command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3 a2 a1 a0 0 1 1 1 0 to 8 bits
mma81xxeg sensors 24 freescale semiconductor 4.6.3 read/write nvm command the read/write nvm command must be tr ansmitted as a dsi long command structure. no action is taken by mma81xxeg/ mma82xxeg/mma82xxteg if this command is se nt to the dsi global device address. there is no response if the read/write nvm command is received within a dsi short command structure. otp data are accessed by fields, where a field is a combination of register address (ra3 - ra0) and bank select (b1, b0) bits. bank select bits are assigned during an initialization or reve rse initialization command. individual bits with predefined funct ions (the upper four bits of devcfg2) each have their own field addr ess. the remaining otp data are grouped into four-bit fields. field addresses are shown in table 4-15 . the structure of the otp array results in data being progra mmed in 16-bit groups. devcfg1 and devcfg2 are in the same group. as a result, a non-zero device address assigned during initialization or reverse init ialization will be permanently programmed into the otp array when any field within the two device configuration bytes is programmed. to avoid programming a non-zero device address, ensure that device address 0 is assigned during initialization or reverse initialization before programming any other bit(s) in devcfg1 or devcfg2. otp programming operations occur when the read/write nvm co mmand is executed after the nv bit has been set during a preceding initialization or reverse initialization command. the minimum dsi bus idle voltage must exceed 14 v when programming the otp array. when this command is executed while the nv bit is cleared, t he dsi device address will be returned regardless of the state of the register address and bank select bits. the read register data command (described in section 4.6.5 ) may be used to access the full range of customer accessible data. table 4-12 read write nvm command structure data address command crc d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 c3 c2 c1 c0 ra3 ra2 ra1 ra0 rd3 rd2 rd1 rd0 a3 a2 a1 a0 1 0 0 1 0 to 8 bits table 4-13 long response structure - read/write nvm command (nv = 1) data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 ra3 ra2 ra1 ra0 1 1 b1 b0 rd3 rd2 rd1 rd0 0 to 8 bits table 4-14 long response structure - read/write nvm command (nv = 0) data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 0 1 1 1 1 a3 a2 a1 a0 0 to 8 bits
mma81xxeg sensors freescale semiconductor 25 4.6.4 format control command the format control command must be transmitted as a dsi long comma nd structure. no change to the format registers occurs if the format control command is receiv ed within a dsi short command structure. if this command is sent to the dsi global device address, the format registers are updated, however there is no response. the format control command conforms to the dsi 2.0 specification. 4.6.4.1 format register read/write control bit (r/w) 1 - write format control register selected by fa2 - fa0 0 - read format control register unless global command table 4-15 otp field assignments register address bank select register definition ra3 ra2 ra1 ra0 b1 b0 0 1 1 0 0 1 devcfg1[3:0] user defined 1 0 devcfg1[7:4] 0 1 1 1 0 0 devcfg2[7] lock2 0 1 devcfg2[3:0] dsi bus device address 1 0 devcfg2[5] glde 1 1 devcfg2[6] par2 1 0 0 0 0 1 reg8[3:0] user defined 1 0 reg8[7:4] 1 0 0 1 0 1 reg9[3:0] user defined 1 0 reg9[7:4] 1 0 1 0 0 1 rega[3:0] user defined 1 0 rega[7:4] 1 0 1 1 0 1 regb[3:0] user defined 1 0 regb[7:4] 1 1 0 0 0 1 regc[3:0] user defined 1 0 regc[7:4] 1 1 0 1 0 1 regd[3:0] user defined 1 0 regd[7:4] 1 1 1 0 0 1 rege[3:0] user defined 1 0 rege[7:4] 1 1 1 1 0 1 regf[3:0] user defined 1 0 regf[7:4] 1 1 devcfg[4] ddis table 4-16 format control command structure data address command crc d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 c3 c2 c1 c0 r/w fa2 fa1 fa0 fd3 fd2 fd1 fd0 a3 a2 a1 a0 1 0 1 0 0 to 8 bits
mma81xxeg sensors 26 freescale semiconductor 4.6.4.2 format control register selection (fa2 - fa0) this three-bit field selects one of eight format contro l registers. format control registers are described in section 4.6.4.3 . there is no response if the format control command is received within a dsi short command structure. 4.6.4.3 format control registers the seven 4-bit format control registers defined in the dsi 2.0 bus specification are shown in table 4-18 below. the default val- ues assigned to each register following reset are indicated. the following restrictions apply to format control register operations, in accordance with the dsi 2.0 bus specification: ? attempting to write a value greater than eight to the crc leng th register will cause the writ e to be ignored. the contents of the register will remain unchanged. ? attempting to write a value less than eight to the short word data length register will caus e the write to be ignored. the contents of the register will remain unchanged. ? the contents of the format selection register determine w hether standard dsi values or the values contained in the remaining format control registers will be used. the values contained in the remaining fo rmat control registers become effective when this register is successfully written to ?1111?. if the register is currently cleared, and one of the data bits fd3 - fd0 is not received as a logic ?1?, the data in the register will remain all zeroes and the device will continue to use standard dsi format settings. if the register bits fd3 - fd0 are a ll set and one of the bits is received as a logic ?0? value, the data in the register will remain ?1111? and the values c ontained in the remaining format control registers will continue to be used. table 4-17 long response structure - format control command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 1 1 0 r/w fa2 fa1 fa0 fd3 fd2 fd1 fd0 0 to 8 bits table 4-18 format control registers format control register default value name address decimal fa2 fa1 fa0 fd3 fd2 fd1 fd0 crc polynomial - low nibble 0 0 0 0 0 0 0 1 crc polynomial - high nibble 1 0 0 1 0 0 0 1 seed - low nibble 2 0 1 0 1 0 1 0 seed - high nibble 3 0 1 1 0 0 0 0 crc length (0 to 8) 4 1 0 0 0 1 0 0 short word data length (8 to 15) 5 1 0 1 1 0 0 0 reserved 6 1 1 0 0 0 0 0 format selection 7 1 1 1 0 0 0 0
mma81xxeg sensors freescale semiconductor 27 4.6.5 read register data command the read register data command must be transmitted as a dsi long command structure. there is no response if the read register data command is rece ived within a dsi short command structure or if this command is sent to the dsi global device address. the sixteen registers shown in table 3-1 may be accessed using this command. regi ster address combinations are listed below. table 4-19 read register data command structure data address command crc d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 c3 c2 c1 c0 0 0 0 0 ra3 ra2 ra1 ra0 a3 a2 a1 a0 1 0 1 1 0 to 8 bits table 4-20 long response structure - read register data command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 ra3 ra2 ra1 ra0 rd7 rd6 rd5 rd4 rd3 rd2 rd1 rd0 0 to 8 bits table 4-21 read register data command address assignment ra3 ra2 ra1 ra0 register 0 0 0 0 sn0 0 0 0 1 sn1 0 0 1 0 sn2 0 0 1 1 sn3 0 1 0 0 type 0 1 0 1 reserved 0 1 1 0 devcfg1 0 1 1 1 devcfg2 1 0 0 0 reg-8 1 0 0 1 reg-9 1 0 1 0 reg-a 1 0 1 1 reg-b 1 1 0 0 reg-c 1 1 0 1 reg-d 1 1 1 0 reg-e 1 1 1 1 reg-f
mma81xxeg sensors 28 freescale semiconductor 4.6.6 disable self-test stimulus command the disable self-test stimulus command may be transmitted as either a dsi long command structure or a dsi short command structure of any length. the data fiel d in the command structure is ignored but is included in the crc calculation. this command will execute if either the device specific address or dsi global device address (address $0) is provided. a secondary function, self-test lockout, is activated when two consecutive disable self-test st imulus commands are received. following self-test lockout, the internal self-test circuitry is disabled until a clear command is received or the device under goes power-on reset. 4.6.7 enable self-test stimulus command the enable self-test stimulus command may be transmitted as either a dsi long command stru cture or a dsi short command structure of any length. the data field in the command structure is ignored but is in cluded in the crc calculation. no action i s taken by the device if this command is sent to the dsi global device address. table 4-22 disable self-test stimulus command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3a2a1a011000 to 8 bits table 4-23 short response structur e - disable self-test stimulus command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 8 nv u st bs at1 at0 s gf 9 0 10 0 11 0 12 0 13 0 14 0 15 0 table 4-24 long response structure - disable self-test stimulus command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf 0 to 8 bits table 4-25 enable self-test stimulus command structure address command crc a3 a2 a1 a0 c3 c2 c1 c0 a3 a2 a1 a0 1 1 0 1 0 to 8 bits
mma81xxeg sensors freescale semiconductor 29 if self-test locking has been activated, the st bit will be cleared in the response from the device. self-test locking is descr ibed in section 4.6.6 . 4.6.8 reverse init ialization command the reverse initialization command conforms to the description provided in section 6.2.1 of the dsi bus standard, version 2.0. at power-up the device is fully compliant with the dsi 1.1 prot ocol. the initialization command must be transmitted as a dsi 1. 1 compliant long command structure. features of the dsi 2.0 prot ocol can not be accessed until a valid dsi 1.1 compliant initial- ization sequence is performed and the enhanced m ode format registers are properly configured. figure 4-1 illustrates the sequence of operations performed following negation of internal power-on reset (por) and execution of a dsi reverse initialization command. reverse initialization commands are recognized only at busout. the busin node is tested for a bus short to battery high voltage condition, and the bus fault (bf) flag set if an error condition is detected. if no bus fault condition is detected and the bs bit is set in the command structure, th e bus switch will be closed. if the device has been pre-programmed, pa3 - pa0 and a3 - a0 must match the pre-programmed address. if no device address has been previously programmed into the otp array, pa3 - pa0 c ontain the device address, while a3 - a0 must be zero. if any addressing condition is not met, the device address is not assi gned, the bus switch will remain open and the device will not re - spond to the reverse initialization command. if the bs bit is se t, the dsi bus voltage level is disregarded for approximately 180 s following reverse initialization to allow hold capacitors on downstream slaves to charge. in the response, bits d15 - d12 and d3 - d0 will contain the dev ice address. if the device was unprogrammed when the reverse initialization command was issued, the device address is assigned as the command executes. both fields will contain the value pa3 - pa0 to indicate successf ul device address assignment. initialization or reverse initialization commands which attempt to assign device address zero are ignored. table 4-26 short response structure - enable self-test stimulus command response length response d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 8 nv u st bs at1 at0 s gf 9 0 10 0 11 0 12 0 13 0 14 0 15 0 table 4-27 long response structure - enable self-test stimulus command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 0 nv u st bs at1 at0 s gf 0 to 8 bits table 4-28 reverse initialization command structure data address command crc d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 c3 c2 c1 c0 nv bs b1 b0 pa3 pa2 pa1 pa0 a3 a2 a1 a0 1 1 1 1 4 bits table 4-29 long response structure - reverse initialization command data crc d15 d14 d13 d12 d11 d10 d9 d8 d7 d6 d5 d4 d3 d2 d1 d0 a3 a2 a1 a0 0 0 0 bf nv bs b1 b0 a3 a2 a1 a0 4 bits
mma81xxeg sensors 30 freescale semiconductor section 5 performance specifications 5.1 maximum ratings maximum ratings are the extreme limits to which the device can be exposed without permanen tly damaging it. the device contains circuitry to protect the inputs a gainst damage from high static voltages; howe ver, do not apply voltages higher than t hose shown in the table below. 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale impor tant characteristic. table 5-1 ref rating symbol value unit 1 2 supply voltages h cap busin, busout v hcap v bus -0.3 to +40 -0.3 to +40 v v (3) (3) 3 voltage at programming/test mode entry pin v pp /test -0.3 to +11 v (3) 4 voltage at c reg , d in , clk, c fil , d out v in -0.3 to +3.0 v (3) 5 voltage at v gnd v gnd -0.3 to +3.0 v (3) 6 7 busin, busout, busrtn and h cap current maximum duration 1 s continuous i in i in 400 200 ma ma (3) (3) 8 current drain per pin excluding v ss , busin, busout, busrtn i 10 ma (3) 9 10 11 acceleration (without hitting internal g-cell stops) z-axis g-cell x-axis g-cell (40g, 70g) x-axis g-cell (100g - 250g) g max g max g max 1400 950 2200 g g g (3) (3) (3) 12 powered shock (six sides, 0.5 ms duration) g pms 1500 g (3) 13 unpowered shock (six sides, 0.5 ms duration) g shock 2000 g (3) 14 drop shock (to concrete surface) h drop 1.2 m (3) 15 16 17 electrostatic discharge human body model (hbm) charge device model (cdm) machine model (mm) v esd v esd v esd 2000 500 200 v v v (3) (3) (3) 18 19 temperature range storage junction t stg t j -40 to +125 -40 to +150 c c (3) (3)
mma81xxeg sensors freescale semiconductor 31 5.2 thermal characteristics 5.3 operating range the operating ratings are the limits normally expected in the application and defi ne the range of operation. 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale impor tant characteristic. 5. minimum operating voltage may be reduced pending characterization. 6. device fully characterized at +105 c and +125 c. production units tested +105 c, with operation at +125 c guaranteed through correlation with characterization results. 9. maximum voltage characterized. minimum voltage tested 100% at final test. maximum voltage tested 100% to 24 v at final test. ref characteristic symbol min typ max units 20 thermal resistance ja jc ? ? ? ? 85 46 c/w c/w (3) (3) ref characteristic symbol min typ max units 21 22 supply voltage (note 9) v hcap (note 5) busin, busout v hcap v bus v l 6.3 -0.3 ? ? v h 30 30 v v (1) (1) 23 24 25 v hcap undervoltage detection (see figure 5-1 ) undervoltage detection threshold v hcap recovery threshold hysteresis (v lvr - v lvd ) v lvd v lvr v lvh ? ? ? ? ? 100 6.2 6.3 ? v v mv (1) (1) (3) 26 27 28 c reg undervoltage detection (see figure 5-2 ) undervoltage detection threshold c reg recovery threshold hysteresis (v lvr - v lvd ) v lvd v lvr v lvh ? ? ? 2.25 2.35 100 ? ? ? v v mv (3) (3) (3) 29 test mode activation voltage v test 4.5 ? 10 v (3) 30 31 programming voltage via spi via dsi v pp /test v bus 7.5 14 8.0 ? 8.5 30 v v (3) (3) 32 otp programming current i prog ? ? 85 ma (3) 33 operating temperature range standard temperature range t a t l -40 ? t h +125 c (6)
mma81xxeg sensors 32 freescale semiconductor 5.4 electrical characteristics the unit digit is defined to be 1 least significant bit (lsb) of the 10-bit digi tal value, or 1 lsb of the equivalent 8-bit value if explicit ly stated. v l (v bus - v ss ) v h , v l (v hcap - v ss ) v h ,t l t a t h , unless otherwise specified. . 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale impor tant characteristic. 7. tested 100% at 10-bit output. 8-bit value verified via scan. 8. functionality verified 100% via scan. ref characteristic symbol min typ max units 34 35 36 37 38 39 40 41 42 43 44 45 46 47 digital output sensitivity 20g range 40g range 50g range 100g range 150g range 250g range c fil output sensitivity (t a = 25 c) 20g range 40g range 50g range 100g range 150g range 250g range sensitivity error t a = 25 c t l t a t h * * * * * * * * * * * * * * sens sens sens sens sens sens sens sens sens sens sens sens sens sens ? ? ? ? ? ? ? ? ? ? ? ? -5 -7 0.0488 0.0976 0.122 0.244 0.366 0.610 20.1 10.0 8.02 4.01 2.67 1.60 0 0 ? ? ? ? ? ? ? ? ? ? ? ? +5 +7 g/digit g/digit g/digit g/digit g/digit g/digit mv/v/g mv/v/g mv/v/g mv/v/g mv/v/g mv/v/g % % (7) (7) (7) (7) (7) (7) (3) (3) (3) (3) (3) (3) (1) (1) 48 49 50 51 offset (measured in 0g orientation) t a = 25 c (8-bit) t l t a t h (8-bit) t a = 25 c (10-bit) t l t a t h (10-bit) * * off 8 off 8 off 10 off 10 122 116 488 464 128 128 512 512 134 140 536 560 digit digit digit digit (7) (7) (1) (1) 52 53 54 55 56 57 full-scale range, including sensitivity and offset errors 20g range 40g range 50g range 100g range 150g range 250g range fsr fsr fsr fsr fsr fsr 21.0 42.0 52.5 105 158 263 24.9 49.9 62.3 124.7 187 312 26.6 53.4 66.7 133 200 334 g g g g g g (3) (3) (3) (3) (3) (3) 58 59 60 range of output normal (10-bit) normal (8-bit) fault range range fault 1 1 ? ? ? 0 1023 255 ? digit digit digit (3) (3) (8) 61 nonlinearity measured at c fil output, t a = 25 cnl out -1 0 +1 % (3) 62 63 64 65 66 67 internal voltage regulator output voltage line regulation load regulation (i reg < 6 ma) ripple rejection (dc f ripple 10 khz, c reg 0.9 f) c reg capacitance effective series resistance, c reg capacitor v creg reg line reg load rr c reg esr 2.37 ? 0.45 60 0.9 ? 2.5 ? ? ? ? ? 2.63 6 2 ? ? 700 v mv mv/ma db f m (1) (3) (3) (3) (3) (3)
mma81xxeg sensors freescale semiconductor 33 5.5 electrical characteristics (continued) v l (v bus - v ss ) v h , v l (v hcap - v ss ) v h ,t l t a t h , unless otherwise specified. . 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale impor tant characteristic. 10. the external circuit configuration shown in section 1.3.6 is recommended. ref characteristic symbol min typ max units 68 69 input voltage low (clk,d in ) high (clk,d in ) v il v ih ? 0.7xv creg ? ? 0.3xv creg ? v v (3) (3) 70 71 output voltage (i out = 200 a) low (d out ) high (d out ) v ol v oh ? v creg - 0.1 ? ? v ss + 0.1 ? v v (3) (3) 72 73 74 output loading, c fil pin (note 10) resistance to v creg , v ss capacitance to v creg , v ss output voltage range r load c load v out 50 ? v ss + 50 mv ? ? ? ? 20 v creg -50mv k pf v (3) (3) (3) 75 bus switch resistance * r sw ?4.08.0 (1) 76 rectifier forward resistance * r fwd ??2.5 (3) 77 rectifier leakage current * i rlkg ? ? 100 a(1) 78 79 80 81 busin or busout to h cap rectifier voltage drop (v bus = 26 v) i busin or i busout = -15 ma i busin or i busout = -100 ma (vbus = 7 v) i busin or i busout = -15 ma i busin or i busout = -100 ma * * v rect v rect v rect v rect ? ? ? ? ? ? ? ? 1.0 1.2 1.0 1.2 v v v v (3) (3) (1) (1) 82 83 busin + busout bias current v busin or v busout = 8.0 v, v hcap = 9.0 v v busin or v busout = 0.5 v, v hcap = 24 v * i bias i bias ? ? ? ? 100 20 ma a (1) (1) 84 85 busin and busout logic thresholds signal low signal high * * v thl v thh 2.7 5.4 3.0 6.0 3.3 6.6 v v (1) (1) 86 87 busin and busout hysteresis signal frame * * v hyss v hysf 30 100 ? ? 90 300 mv mv (3) (3) 88 busin + busout response current v busin and/or v busout = 4.0 v * i resp 9.9 11 12.1 ma (1) 89 quiescent current * i q ? ? 7.5 ma (1) 90 internal pull-down resistance clk r pd 20 60 100 k (2) 91 internal pull-down resistance v pp /test r pd 437 k (2) 92 93 gnd loss detect (with external 3 k resistor) measurement current detection resistance i gndetc r gnddetc 309 1 340 ? 371 10 a k (1) (1)
mma81xxeg sensors 34 freescale semiconductor 5.6 electrical characteristics (continued) v l (v bus - v ss ) v h , v l (v hcap - v ss ) v h ,t l t a t h , unless otherwise specified. . 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale impor tant characteristic. 7. tested 100% at 10-bit output. 8-bit value verified via scan. ref characteristic symbol min typ max units 94 95 96 97 total noise (see figure 5-3 ) 400 hz, 4-pole filter, 20g range rms, 100 samples p-p, 100 samples 180 hz, 2-pole filter, 20g range rms, 100 samples p-p, 100 samples n rms n p-p n rms n p-p ? ? ? ? ? ? ? ? 2 8 2 7 digit digit digit digit (3) (3) (3) (3) 98 99 100 101 cross-axis sensitivity x-axis, x-axis to y-axis x-axis, x-axis to z-axis y-axis, y-axis to x-axis y-axis, y-axis to z-axis v xy v xz v yx v yz -5 -5 -5 -5 ? ? ? ? +5 +5 +5 +5 % % % % (3) (3) (3) (3) 102 103 104 105 106 107 analog to digital converter relative accuracy differential nonlinearity gain error offset error (v in = v creg /2) noise (rms, 100 samples) noise (peak) inl dnl gainerr ofst n rms n p-p -2 -1 -1 -3 -1 -3 ? ? ? ? ? ? +2 +1 +1 +3 +1 +3 digit digit %fsr digit digit digit (3) (3) (2) (3) (3) (3) 108 109 110 111 112 113 114 115 116 117 deflection (self-test output - offset, average of 30 samples, measured in 0g orientation, t a = 25 c) x-axis, 20g range x-axis, 40g range x-axis, 50g range x-axis, 100g range x-axis, 150g range x-axis, 250g range z-axis, 40g range z-axis, 100g range z-axis, 150g range z-axis, 250g range * * * * * * * * * * dflct dflct dflct dflct ddflct ddflct dflct dflct dflct dflct ? ? ? ? ? ? ? ? ? ? 246 123 98 49 82 49 307 299 205 123 ? ? ? ? ? ? ? ? ? ? digit digit digit digit digit digit digit digit digit digit (7) (7) (7) (7) (7) (7) (7) (7) (7) (7) 118 self-test deflection range, t a = 25 c, measured in 0g orientation dflct -10 ? +10 % (1) 119 self-test deflection range, t l t a t h , measured in 0g orientation dflct -20 ? +20 % (1)
mma81xxeg sensors freescale semiconductor 35 figure 5-1. v hcap undervoltage detection figure 5-2. v creg undervoltage detection gnd v lvr v hcap v lvd undervoltage v lvh resumes operation normal t uvr uv uv: undervoltage condition exists uv por asserted por negated gnd v lvr v creg v lvd low-voltage condition detected por negated v lvh internal reset is initially asserted until v creg v lvr , and thereafter when v creg v lvd . resumes operation normal por asserted
mma81xxeg sensors 36 freescale semiconductor figure 5-3. total noise measurement conditions 20 s a3 a2 a0 a1 0 0 1 0 0 0 0 0 0 0 0 0 0 0 a3 a2 a0 a1 c3 c2 c1 c0 d1 d0 d3 d2 d5 d4 d7 d6 d9 d8 command format cmd 99 cmd 100 cmd 1 cmd 2 resp 98 resp 99 xxx resp 1 xxx resp 100 cmd 3 resp 2 90 s measurement window (10910 s) measurement timing uut busin busout busrtn n/c dol doh dsi bus configuration master
mma81xxeg sensors freescale semiconductor 37 5.7 control timing v l (v bus - v ss ) v h , v l (v hcap - v ss ) v h ,t l t a t h , unless otherwise specified. 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale important characteristics. 8. functionality verified 100% via scan. timing is di rectly determined by internal oscillator frequency. ref characteristic symbol min typ max units 120 vhcap undervoltage reset period (see figure 5-1 ) v hcap < v ra to por assertion t uvr 0.95 1.0 1.05 ms (8) 121 122 123 analog to digita l converter (see figure 5-4 ) sample time conversion time delay following bus idle t sample t convert t delay 4.28 7.13 2.85 4.5 7.5 3.0 4.73 7.88 3.15 s s s (8) (8) (8) 124 busin and busout response current transition 1.0 ma to 9.0 ma, 9.0 to 1.0 ma t itr 4.5 ? 7.5 ma/ s(3) 125 initialization to bus switch closing t bs 89 ? 138 s(3) 126 signal bit transition time t bit 5?200 s(3) 127 loss of signal reset time maximum time below frame threshold t to ??10ms(8) 128 129 busin or busout timing to response current busin or busout v thl to i bus 7 ma busin or busout v thh to i bus 5 ma t rsph t rspl ? ? ? ? 3.0 3.0 s s (3) (3) 130 131 132 133 interframe separation time (see figure 5-5 ) following read write nvm command following initialization or reverse initialization bs = 1 bs = 0 following other dsi bus commands t ifs t ifs t ifs t ifs 2 200 20 20 ? ? ? ? ? ? ? ? ms s s s (3) (3) (3) (3) 134 135 low pass filter (4-pole, -3 db rolloff frequency) (2-pole, -3 db rolloff frequency) bw out bw out 360 162 400 180 440 198 hz hz (1) (1) 136 137 ground loss detection filter time cycles of f osc time t gndetc t gndetc ? 16384 4.096 ? cycles ms (8) (8) 138 139 140 reset recovery time por negated to initialization command por negated to 180 hz data valid por negated to 400 hz data valid t reset t reset t reset ? ? ? ? 5.3 2.4 100 ? ? s ms ms (8) (3) (3) 141 internal oscillator frequency f osc 3.80 4.0 4.20 mhz (1) 142 143 logic duty cycle logic ?0? logic ?1? * * d cl d ch 10 60 33 67 40 90 % % (8) (8) 144 otp programming, spi program control t prog ?? 2ms(8)
mma81xxeg sensors 38 freescale semiconductor 5.8 control timing (continued) v l (v bus - v ss ) v h , v l (v hcap - v ss ) v h ,t l t a t h , unless otherwise specified. 1. parameters tested 100% at final test. 2. parameters tested 100% at unit probe. 3. verified by characterizati on, not tested in production. 4. (*) indicates a customer critical characteri stic or freescale important characteristics. 8. functionality verified 100% via scan. timing is di rectly determined by internal oscillator frequency. ref characteristic symbol min typ max units 145 146 147 148 spi timing (see figure 5-6 ) clk period d in to clk setup clk to d in hold clk to d out t clk t dc t cdin t cdout 500 50 50 ? ? ? ? ? ? ? ? 20 ns ns ns ns (3) (3) (3) (3) 149 150 151 sensing element resonant frequency z-axis g-cell x-axis medium-g g-cell (20-50g) x-axis high-g g- cell (100-250g) f gcell f gcell f gcell ? 11.2 18.0 22.0 12.8 20.6 ? 15.3 24.2 khz khz khz (3) (3) (3) 152 153 154 sensing element rolloff frequency (-3 db) z-axis g-cell x-axis medium-g g-cell (20-50g) x-axis high-g g- cell (100-250g) bw gcell bw gcell bw gcell ? ? ? 1.58 19 32 ? ? ? khz khz khz (3) (3) (3) 155 156 gain at package resonance z-axis x-axis q q ? ? 10 12 ? ? khz khz (3) (3) 157 158 package resonance z-axis x-axis f f ? ? 45 9.5 ? ? khz khz (3) (3)
mma81xxeg sensors freescale semiconductor 39 figure 5-4. a-to-d conversion timing figure 5-5. dsi bus interframe timing figure 5-6. serial interface timing busin stabilization s/h conversion t delay t sample t convert busin t ifs dsi bus command t clk t dc t cdin clk d in /v gnd d out t cdout data valid
mma81xxeg sensors 40 freescale semiconductor appendix a test mode operation test mode is entered when certain conditions are satisfied after power is applied to the device. communication with the device is conducted using the spi when in test mo de. two test mode operations are of intere st to the customer. these operations are described below. test mode communication is cond ucted using the serial peripheral interface (spi). a.1 spi data transfer a 16-bit spi is available for data transfer when the voltage at v pp /test is raised above v test . test mode is entered when the sequence of data values shown above are transferred following reset. see figure a-4 for details of 16-bit spi packet. the state of d in is latched on the rising edge of clk. d out changes on the falling edge of clk. the interface conforms to cpha = 0, cpol = 0 operation for conventional spi devices. a.2 adc test mode a special device configuration useful for ev aluating the performance of th e analog-to-digital convertor block is available. whe n selected, internal buffers which drive the c fil pin and adc input are disabled, and the i nput of the adc is connected to the c fil pin, as illustrated in figure a-1. the following sequence of operations must be performed to enter adc test mode. refer to appendix a.4 for details regarding register read and write operations. 1. apply v hcap to the h cap pin. this may be accomplished through busin if desired. 2. apply v test to the v pp /test pin. 3. transfer the data value $aa to device register address $30 via the spi. 4. transfer the data value $55 to device register address $30 via the spi. 5. transfer the data value $1d to device register address $30 via the spi. remove power or lower the voltage at v pp /test to exit adc test mode.
mma81xxeg sensors freescale semiconductor 41 figure a-1. adc test mode configuration busout busin busrtn logic command decode state machine response generation bandgap reference oscillator g-cell c-to-v converter low-pass filter offset trim gain trim tcs trim selftest trim osc trim selftest voltage self-test enable voltage regulator c reg h cap internal supply voltage otp programming interface v pp /test d out clk c fil v ss c reg v ss n/c a-to-d converter regulator trim 16 15 14 11 12 9 8 6 5 4 3 13 1 v ss 10 n/c 2 v gnd /d in ground loss detector 7
mma81xxeg sensors 42 freescale semiconductor a.3 otp programming operations the ten customer-programmed otp loca tions (devcfg0, devcfg1 and reg-8 th rough reg-f) may be programmed when the device is in test mode if the following sequence of operati ons is performed. register access operations required for otp pr o- gramming are described in appendix a.4 . 1. apply v hcap to the h cap pin. this may be accomplished through busin if desired. 2. apply v test to the v pp /test pin. 3. write the desired data values to the two registers via the spi. 4. transfer the data value $aa to device register address $30 via the spi. 5. transfer the data value $55 to device register address $30 via the spi. 6. transfer the data value $c6 to device register address $30 via the spi. 7. write the data value $00 to address $20 via the spi. this will enable write access to the fuse mirror registers. 8. write register data to be programmed into fuse array. 9. write the data value $05 to address $20 via the spi. the aut omatic programming sequence is initiated by this write operation. 10. delay a minimum of 32 s to allow the programming sequence to begin. 11. read data value from address $29 until bit 5 is set. 12. if bit 4 of value read from address $29 is set, th e programming operation did not complete successfully. bits which are unprogrammed may be programmed to a logic ?1? st ate. the device may be increm entally programmed if desired, however once a bit is programmed to a logic ?1? state, it may no t be reset to logic ?0? in the otp array. once the lock2 bit ha s been set, no further changes to the otp array are possible. settin g lock2 also enables parity detection when the device oper- ates in normal mode. a.4 internal register access using the din /vgnd, clk, and dout pins, each addre ss location of mma81xxeg/mma 82xxeg/mma82xxteg can be read and written from an external spi interface shown in figure a-2. the corresponding registers may be used to: ? program the otp memory ? read the otp memory ? access various internal sign als of the mma81xxeg/mma82xxeg /mma82xxteg in test mode figure a-2. otp interface overview clk d out d in /v gnd serial peripheral interface register array otp array to digital interface
mma81xxeg sensors freescale semiconductor 43 a.4.1 interface data bit stream the 16-bit spi serial data consists of 6 bits for a data address, 1 bit for a data direction, and 8 bits for the data to be tra nsferred as shown below. figure a-3. serial data stream a[5:0] register array location to be read or written. d[7:0] register array data. this is the data to be transferred to th e register array during write oper ations, or the data contained in the array at the associated address during read operations. rw control of data direction during the clo cking of d[7:0] data bits as follows: rw = 1 register array write. d[7:0] are transferred into the regi ster array during subsequent transitions of the clk input. rw = 0 register array read. data are transferred from the regi ster array during subsequent tr ansitions of the clk input. a.4.2 register array read operation read operations are completed through16-bit tr ansfers using the spi as shown below. data contained in the array at the asso- ciated address are presented at the d out pin during the 8th through 15th falling edges at the clk input. figure a-4. serial data timing, register array read operation should the data transfer be corrupted by e. g., noise on the clock line, a device reset is required to restore the state of inte rnal logic. a[5] 15 bit function a[4] 14 a[3] 13 a[2] 12 a[1] 11 a[0] 10 rw 9 ? 8 d[7] 7 d[6] 6 d[5] 5 d[4] 4 d[3] 3 d[2] 2 d[1] 1 d[0] 0 a[5] a[4] a[3] a[2] a[1] a[0] rw d[6] d[5] d[4] d[3] d[2] d[1] d[0] d[7] 12345678 910111213141516 clk d in /v p2 d out
mma81xxeg sensors 44 freescale semiconductor a.4.3 register array write operation a write operation is completed through the transfer of a 16-bit value using the spi as shown in the diagram below. data present at the d in pin are transferred to the register at the associated address during the 9th through 16th rising edges at the clk input. contents of the register at t he time the write operation is in itiated are presented at the d out pin during the 8th through 15th falling edges of the clk input. figure a-5. serial data timing, register array write operation a.4.4 internal address map overview otp data is transferred to internal registers during the firs t sixteen clock cycles following oscillator startup and negation o f internal reset. when the device ope rates in test mode, otp data in the mirror registers may be overwritt en. mirror register writes must be enabled by setting the spi_write_enable bit (address $29[5]). this bit may be set by writing the value $0 to address $20. internal register read and write operations are described in section 3 . a[5] a[4] a[3] a[2] a[1] a[0] rw d[6 d[5] d[4] d[3] d[2] d[1] d[0] d[7] 12345678 910111213141516 clk d in /v p2 d[6] d[5] d[4] d[3] d[2] d[1] d[0] d[7] d out
mma81xxeg sensors freescale semiconductor 45 package dimensions
mma81xxeg sensors 46 freescale semiconductor package dimensions
mma81xxeg rev 5 04/2010 rohs-compliant and/or pb-free versions of freesca le products have the functionality and electrical characteristics of their non-rohs-compliant and/or non-pb-free counterparts. for further information, see http:/www.freescale.com or contact your freescale sales representative. for information on freescale?s environmental products program, go to http://www.freescale.com/epp. how to reach us: home page: www.freescale.com web support: http://www.freescale.com/support usa/europe or locations not listed: freescale semiconductor, inc. technical information center, el516 2100 east elliot road tempe, arizona 85284 1-800-521-6274 or +1-480-768-2130 www.freescale.com/support europe, middle east, and africa: freescale halbleiter deutschland gmbh technical information center schatzbogen 7 81829 muenchen, germany +44 1296 380 456 (english) +46 8 52200080 (english) +49 89 92103 559 (german) +33 1 69 35 48 48 (french) www.freescale.com/support japan: freescale semiconductor japan ltd. headquarters arco tower 15f 1-8-1, shimo-meguro, meguro-ku, tokyo 153-0064 japan 0120 191014 or +81 3 5437 9125 support.japan@freescale.com asia/pacific: freescale semiconductor china ltd. exchange building 23f no. 118 jianguo road chaoyang district beijing 100022 china +86 10 5879 8000 support.asia@freescale.com for literature requests only: freescale semiconductor lite rature distribution center 1-800-441-2447 or +1-303-675-2140 fax: +1-303-675-2150 ldcforfreescalesemiconductor@hibbertgroup.com information in this document is provided solely to enable system and software implementers to use freescale semiconduc tor products. there are no express or implied copyright licenses granted hereunder to design or fabricate any integrated circuits or integrated circuits based on the information in this document. freescale semiconductor reserves the right to make changes without further notice to any products herein. freescale semiconductor makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does freescale semiconductor assume any liability ar ising out of the application or use of any product or circuit, and specifically discl aims any and all liability, including without limitation consequential or incidental damages. ?typical? parameters that may be provided in freescale semiconductor data s heets and/or specifications can and do vary in different applications and actual performance may vary over time. all operating parameters, including ?typicals?, must be validated for each customer application by customer?s technical experts. freescale se miconductor does not convey any license under its patent rights nor the rights of others. freescale semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the fa ilure of the freescale semiconductor product could create a situation where personal injury or death may occur. should buyer purchase or use freescale semiconductor products for any such unintended or unauthorized application, buyer shall indemni fy and hold freescale semiconductor and its officers, employees, subsidiaries, affili ates, and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death associated with such unintended or unauthorized use, even if such claim alleges that freescale semiconductor was negligent regarding the design or manufacture of the part. freescale and the freescale logo are trademarks of freescale semiconductor, inc., reg. u.s. pat. & tm. off. all other product or service names are the property of their respective owners. ? freescale semiconductor, inc. 2010. all rights reserved.

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