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| Data Sheet AS8446 AS 8446 Programmable PWM DC Motor Driver / Controller DATA SHEET Key Features - - Programmable PWM DC Motor Driver / Controller with P Interface (Three Wire Interface) Programmable Functions and Parameters for Motor Current, Voltage and Speed Regulation Single Voltage Supply in the range Vbat = 6.0 V to 18 V (Vbat,max = 30 V) 1 Total Power Efficiency up to 96 % Low RF Emission within the whole frequency range due to an integrated special EMC optimized driver Dynamically self-adjusting slew rate regulated switching technology Fully protected by programmable failure handling procedures via P Fast Over Current and Over / Under Voltage Detection and Protection, Battery Voltage Monitoring External and On Chip Temperature Detection and Protection Motor Current and Speed Measurement with a shunt resistor and capability of trimming the chip for an external shunt value Programmable Parameters: * EMC compliant Driver Functions * Over Current, Over / Under Voltage Threshold Values * Motor Failure Threshold Levels * Motor Current Measurement Range * Trimming for the current measurement shunt WakeUp It is an advanced PWM DC motor controller subsystem with an excellent EMC behavior targeted especially for high current automotive applications. The optimization of the EMC behavior of the entire module only by software changes makes it easier to implement it in harsh environments. The programmability of parameters and functions allows the adaptation of the AS8446 to a wide range of applications. So the system can act either as a motor current or motor speed or motor voltage regulator. Also a full diagnosis of motor failures and power FET failures, over temperature and over/under voltage can be formed by programmable failure handling procedures using the motor characteristic and the real time measured motor current, motor speed and battery voltage. Applications - Fan cooler Air conditioning Fuel pumps Water and oil pumps General purpose DC Motor Regulators Typical Application Diagram Control part Power part Cbat 1 2 3 4 5 Vbat AS8446 - OSC1 VDD CLK GND Port1 Port2 9 10 11 12 Wake-up n.c. Test1 Test2 Iref 20 RESET 19 WD 18 Test3 17 PWM 16 CLK 15 Rref RT1 RNTC Sleep / Wake-up Mode system controlled by the P and the Wake-up Pin SOIC 28 Package CVDD * PWM Frequency, Charge Pump Monitor Charge Pump to control high side drivers Integrated 5 V Power Supply for external components (P, etc.) Standby and Wake-up capability CMN CMP VMO Vbat TP FAIL CS ADC VSS 28 GND_P 27 OUT 26 Tr1 CP12 CP0 Rmeas Vpump 25 CP2 24 CP1 23 VDDctrl 22 VDD 21 VDD = 5 V PWMout INR CS ANA 6 7 8 P (optional) Q1 OSC2 D1 M+ M MVSS RESET Tout SPIout SPIin 13 DATAin 14 DATAout General Description The AS8446 is a complete and fully protected PWM DC motor driver/controller, which can be implemented by interfacing a low cost 8-bit P and a high-side N-channel power FET switch. GND_P 1 Low-Batttery-mode between 6.0 V and 6.5 V Revision 1.8, Date 2005-03-17 Page 1 of 35 Data Sheet AS8446 Functional Description Overview The AS8446 is a complex integrated circuit, which contains both low and high voltage circuitry to regulate PWM brush DC motors with an external n-channel power FET and an 8-bit P. The regulation loop is a closed loop environment where a P is connected to the device with a Three-Wire Interface. The AS8446 measures and delivers the motor current as an analog value to the P. The P uses a special algorithm to calculate the motor speed by considering the motor current as a function of time. This technique allows the system to act either as a motor current or a motor speed regulator. The AS8446 also monitors and delivers the battery voltage to the P as an analog value and by leveraging this voltage-monitoring feature a motor voltage regulator could be implemented also. A full diagnosis of motor and power FET failures is performed automatically by the programmable failure handling functions after carefully analyzing the motor characteristics, real-time motor current, motor speed and battery voltage. The dynamically self-adjusting slew rate regulated switching technology (patented) is one of the most important features of this ASSP in automotive applications. This technology enables two features of the PWM DC motor regulator, which were up till now impossible to realize: * * Excellent EMC behavior (very low RF emission in the whole frequency range) AS8446 into a power save mode. It is controlled via the specified wake-up pin. A short overview of the main features follows. * * * programmable PWM DC motor current, speed or voltage regulator single voltage supply in the range Vbat = 6.0V to 18V (Vbat,max = 30 V) Low-Battery-Mode guarantees operation also when battery voltage is between 6.0V and 6.5V; In this mode the output driver is constantly on (100% PWM), Vpump-Vbat 4.0V. * * * * * * * applicable directly to the automotive battery supply (burst, surge, load dump) closed loop regulation of the motor speed, motor current or motor voltage with a P. high power efficiency of the whole regulator module (up to 96 % @ fPWM = 20 kHz) low RF emission within the whole frequency range fully protected by programmable failure handling procedures (see below: Security Functions) fast over current and over / under voltage detection and protection motor current and motor speed measurement with only one shunt resistor (typ. measurement voltage at nominal motor current: 50 mV) on chip trimming capability of the external shunt resistor Sleep/wake up mode system controlled by the P and the wake-up pin Three Wire Interface programming possibilities of the following regulator parameters inside of the AS8446: * PWM frequency (generated by P, e.g. 20 kHz) charge pump voltage monitoring and protection slew rate control parameters (EMC behavior) power FET Gate driver currents up to 500 mA over current threshold level over / under voltage threshold level motor current measurement range and trimming of the external current measurement resistor programming possibilities of the following regulator * * * * High power efficiency up to 96 % @ fPWM = 20 kHz (fall / rise time down up to < 150 ns) Most of the parameters (e.g. PWM frequency, slew rate, over current threshold, current measurement range, etc.) of the AS8446 can be programmed (setting up the internal registers) through the Three-Wire Interface, which makes the regulator a versatile and easily adaptable device to a wide range of regulation modes and motors. The field programmability option of the slew rate regulation parameters makes it easier to comply with the system level EMC behavior (regulator board, motor, power cables, etc.) A bandgap is used as a reference for a Low Drop Voltage Regulator with a nominal output voltage of 5 V. This regulator is capable to deliver a supply current of up to 40 mA. Higher current is possible with an external bipolar transistor. The device is bundled with a set of software to handle the regulation loop, motor speed measurement and failure detection. A sleep/wake up system is integrated to bring the parameters / functions via the P motor failure threshold levels (motor currents and voltages) for all motor failures: blocked motor, open wire, no load, shorted motor segments, etc. failure handling procedures for all motor failures, over / under voltage and for over temperature (type of reaction and timing) sleep mode criteria and sleep mode signal to the AS8446 Revision 1.8, Date 2005-03-17 Page 2 of 35 Data Sheet AS8446 - closed loop regulation timing with P for speed, current and voltage control special features e.g. suppression of particular motor speeds, dynamical change of the over current threshold level, etc. Security Functions Extensive diagnosis of the DC motor and the power FET as well as failure handling procedures are programmable via a P. * * * * * * * * * over current detection and protection no load detection of the motor open wire detection (motor or power switch) short circuit of the power switch detection blocked motor detection and protection short circuited motor segments detection and protection protection of the power FET and the AS8446, if the motor works in generator mode battery voltage monitoring and over / under voltage detection and protection two over temperature detection and protection modes external temperature sensor on chip temperature sensor Item (Start up values) Over Voltage Threshold Under Voltage Threshold Minimum Charge Pump Voltage Over Current Threshold (Shunt Measurement Voltage) Mode after Start up AS 8446 40.0 V 2.5 V 4.0 V 125 mV sleep mode Table 1 Start up values of the AS 8446 Revision 1.8, Date 2005-03-17 Page 3 of 35 Data Sheet AS8446 Pin Description The AS8446 Motor Driver/Controller contains the driver/controller chip in a SOIC28 package The complete PWM DC Motor Regulator board needs an additional P to close the regulation loop and control the whole regulator (dual package solution, free choice of the controlling P). Pin Name 1 2 3 4 5 6 CMN CMP VMO Vbat TP FAIL CS ADC Wake-up n.c. Tst 1 Tst 2 DATAin DATAout Clk PWM Tst 3 WD RESET Iref VDD VDDctrl Type HV AI HV AI HV AI S HV AI LV DO LV DIPU HV AO HV AIO LV DIPU LV DO LV DIPD Note Current Measurement Input (negative side) Current Measurement Input (positive side) Motor Voltage Input Battery Voltage, Main Supply Temperature Sensor Input Error Status Output of AS8446 Chip Select, Enable Pin of Three Wire Interface Analog Measurement Output (multiplexed) Wake-up Pin Test Pin 1 (1) Test Pin 2 (2) Data Input of the Three-Wire Interface Pinout AS8446 7 8 1 2 3 4 5 6 7 8 9 10 11 12 13 14 CMN CMP VSS 28 GND_P 27 26 9 10 11 12 13 14 15 16 17 18 19 20 21 22 AS8446 VMO Vbat TP FAIL CS ADC OUT Vpump 25 CP2 24 CP1 23 VDDctrl VDD Iref RESET 22 21 20 19 LV DO_T Data Output of the ThreeWire Interface LV DIPD LV DIPU LV DO LV DIPU LV DO LV AIO AI HV AO Clock of the Three-Wire Interface PWM Input (Control of the Power FET Driver) Test Pin 3 (2) Watch Dog Input Reset Output (controlled by Watch Dog) Reference Current Pin VDD feedback input VDD supply (5 V generated by the on chip voltage regulator) Charge Pump Capacitor (Vbat side) Charge Pump Capacitor (Vpump side) Charge Pump Buffer Capacitor Power FET Driver Output Power Ground Digital/Analog Ground Wake-Up n.c. Tst 1 Tst 2 DATAin DATAout WD 18 Tst 3 17 PWM 16 Clk 15 Figure 1 Pinout AS 8446 Pin Description AS8446, Pin Types S AI AO AIO DI DIPU DIPD DO DIO DO_T LV HV ... ... ... ... ... ... ... ... ... ... power supply analog in analog out analog in/out digital in digital in with pull-up digital in with pull-down digital out digital in/out digital out, tristate 23 24 25 26 27 28 Table 2 CP1 CP2 Vpump OUT GND_P VSS HV AIO HV AIO AO HV AO S S PIN description of AS 8446 ... low voltage ... high voltage Note (1) Must be connected to VDD Note (2) Must be left open Revision 1.8, Date 2005-03-17 Page 4 of 35 Figure 2 CP1 2 CP 0 Data Sheet AS8446 Block Diagram CP1 C P2 V DDH1 Vpu m p RESET R eg is te r 50 kH z C L K pum p a ) s ett ing s b ) c o n trol Iref R C O s c il la t o r D ri v e V D D H = V bat 10 V L o w S id e D A T A in S E T_0 21 12 3 2 CS s lee p S E T _k slew rate (low) programming B it_ 0 S le e p / w a k e PW M 3 M oto r- a n d P ow e r F E T p r o te c tio n P T o v er1 P T o ve r2 D AT Ao ut OR P o ve rc P Vo ver P V un d er prog ra m ma ble : 12 V , 24 V , 4 2 V Rx pd slee p u p s ys te m V o lt a g e M o n it o r in g FA IL B i t_n Self Adjusting Slew Rate Regulation Interface / Control CMp PW M V re fV W a k e -u p V in = V ba t V b a t_ m o n GND programming Tst 1 VD DH V A _ c u r r e n t = kx * Im otor V A _ o v e r c = k y* I m oto r A _ c u r r en t E xte rn a l O ve r T e m p e r a tu r e d e tec tio n V re fT 1 O n ch i p O ve r T e m p e ra tu r e d e te c tio n V re fT 2 CM n Tst 2 p rogra mm ing k6 , k 7 A _ o ve r c PWM r e fe r en c e Tst 3 Vref 5 V - r e g u la t o r ( b a n d g a p r e f .) V r e f/I re f V re f= 1. 0 V VDDH g e n e r a to r b a nd g a p V D D c trl VDD VSS A M VDD a n d t rim m in g (o ver cu rr ent, R m eas ) k5 l ow v o lta ge h ig h v olt a g e P ov e r c H V -IN / L V -O U T TP A _ ove rc AS 8 44 4 u P ba se d D C M oto r R egu la to r ADC Analog MUX ( a n a lo g ) A _ cu rrent V ba t_ mo n a u s t ria m ic r o s y s te m s VSS VDD V D D c tr l CV D D TP R N TC RT1 Rref VD D Ire f G ND _P p a ck a ge : S O IC 2 8 Rmeas W a k e-u p I n te r fa ce Imotor 2 M o to r c u r r en t a n d s p e e d m e a s u r e m e n t / o v e r cu r r en t OUT Vm o S h if t R e g is t e r s slew rate (high) programming Block Diagram of AS8446 C l k_ w d a c tiv e /d e a c tiv e C lk t R/W C on tr ol OR Revision 1.8, Date 2005-03-17 WD S e r ia l PO R H ig h S id e D ri v e V D D H = V b at C h a rg e p u m p V DD H In t e r f a c e W a tc h d og POR VDD wd Page 5 of 35 Data Sheet AS8446 General Application Diagram Control part Power part Cbat 1 2 Vbat CMN CMP VMO Vbat TP FAIL CS ADC Wake-up n.c. Tst1 Tst2 VSS 28 GND_P 27 OUT Tr1 CP12 CP0 Rmeas WakeUp AS8446 3 4 5 26 Vpump 25 CP2 24 CP1 23 VDDctrl 22 VDD 21 Iref 20 RESET 19 WD 18 Tst3 17 PWMout INR CS ANA CLK GND Port1 Port2 6 7 8 9 10 11 12 P (optional) Q1 OSC2 OSC1 VDD VDD = 5 V Rref RT1 RNTC CVDD D1 M+ M MVSS RESET Tout SPIout SPIin 13 DATAin 14 DATAout PWM 16 CLK 15 GND_P Figure 3 General Board Diagram of a complete PWM DC Motor Regulator Remarks: a) b) The communication between the AS8446 and the controlling P is realized via the Three-Wire Interface The communication of the whole motor regulator module with the environment can be realized in different ways: 1. low voltage 5 V digital input using a digital P port 2. low voltage 5 V analog output using an analog ADC input of the P c) d) The EMC parameters to optimize the EMC behavior of the whole regulator system can be stored in the program of the P and transmitted to the AS8446 via Three-Wire Interface during start up of the system. The customer has free choice of the P. Revision 1.8, Date 2005-03-17 Page 6 of 35 Data Sheet AS8446 Absolute Maximum Ratings (NON OPERATING) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings only. Functional operation of the device at these or any other conditions beyond those indicated under Operating Conditions is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. Parameter Battery voltage Pumped voltage Low Power Supply Voltage Input Pin Voltage (Low voltage pins) Input Current (latchup immunity) ESD Total Power dissipation Junction temperature Storage temperature Humidity Body temperature TBody Pvtot Tj Tstg -55 5 Symbol Vbat Vpump VDD Vin Iscr Min -0.3 -0.3 -0.3 -0.3 -100 -0,9 Max 30 44 7 VDD+0.3 100 0,9 500 150 150 85 240 Unit V V V V mA kV mW C C % C Non condensing Norm: IPC/JEDEC J-STD 020 C 125C Norm: MIL 883 E method 3015 (2) Note (1) Note (1): Load Dump, 500ms, according to DIN40839 Note (2): Except for Pin 1 (CMN) and Pin 25 (Vpump): ESD = +/- 0,5 kV Table 3 Absolute Maximum Ratings Operating Conditions Parameter Battery voltage (normal operating-mode) Battery voltage (Low-Batterymode) Pumped voltage Low Voltage Power Supply Standby Current (power down) Standby Current (power down) Ambient temperature Symbol Vbat Vbat Vpump VDD I_pd1Vbat I_pd2Vbat Tamb -40 Min 6.5 6.0 Vbat + 4V 4.8 Vbat + 10V Typ Max 18 6.5 Vbat + 14V 5.15 (50) 90 125 Unit V V V V A A C Note (1) Vpump-Vbat 4.0V; Vout = const. high; (2) (2) (2);(3) Tamb < 27 C; (4) Tamb < 125 C; Vbat = 13.5V Note (1): Jump Start: Vbat < 28V, 1 min, 1 pulse/h Note (2): Low Battery mode guarantees operation when the battery voltage is below 6.5V; In this mode the output driver is constantly on (100% PWM), Vpump-Vbat 4.0V at 250A load on Pin OUT; the load current of VDD is limited to 2.5mA Note (3): Low Drop voltage regulator; 40 mA max. external load at VDD; higher current with external transistor possible Note (4): only as information. Will not be tested Table 4 Operating Conditions Thermal Characteristics Parameter Thermal resistance from junction to ambient Table 5 Thermal Characteristic Symbol Rth,ja Min Max 76.2 Unit Note C/W free air, single layer PCB Revision 1.8, Date 2005-03-17 Page 7 of 35 Data Sheet AS8446 Characteristics for Analog and Digital Inputs and Outputs CMOS LV Digital Input Pins: Clk, DATAin, CS, PWM, WD Parameter High Level Input Voltage Low Level Input Voltage Input Leakage Current Table 6 CMOS Input parameters Symbol VIH VIL ILEAK Min 0.7 * VDD Max 0.3 * VDD Unit V V A Note -1 1 pull-up/down current for inputs with pull-up/down typ. 60A CMOS LV Digital Output Pins: RESET, DATAout, FAIL Parameter High Level Output Voltage Low Level Output Voltage Table 7 CMOS Output parameters Symbol VOH VOL Min VDD -0.5 Max VSS +0.4 Unit V V Note CLOAD = 50 pF CLOAD = 50 pF Analog Signals Input / Output Pins: Vpump, CP1, CP2, OUT, CMP, CMN, VMO, ADC, TP, Iref Parameter, Pin Name Charge Pump Voltage, pin: Vpump Charge pump switched capacitor voltage, pin: CP1 Charge pump switched capacitor voltage, pin: CP2 HS driver source current, pin: OUT HS driver sink current, pin: OUT Motor current measurement inputs, Common mode range, pins: CMP, CMN Motor voltage input, pin: VMO Analog measurement output voltage, pin: ADC External temperature sensor input, threshold voltage, pin: TP Reference current generation voltage, pin: Iref Note (1): Note (2): Note (3): Pin type HV S HV AIO HV AIO HV AO HV AO HV AI HV AI LV AO LV AI LV AI Symbol Vpump VCP1 VCP2 Iout_p Iout_n VCMP, VCMN VVMO VA_current VTP_th Vref Min Vbat + 6 Vbat + 4 VSS VSS -500 Typ Vbat + 10 Max Vbat + 14 Vbat Vbat + 14 Unit V V V mA Note (1) (2) (2) 500 -1.5 -1.5 0 0 0.5 VDD 1.0 Vbat Vbat VDD VDD mA V V V V V Multiplexed analog output (3) Threshold voltage: VDD / 2 (4) external capacitors CP1/2 = 100 nF, CP0 = 400 nF recommended; on chip Vpump monitoring and protection: Vpump_min = (Vbat + 6 V) or (Vbat + 4 V), programmable typical rise/ fall time at the external Power MOSFET source: 0.2 s to 0.5 s, independently programmable rise and fall times, voltage range of the voltage VOUT = 0 ... Vpump Multiplexed output (controlled by register R15<3:0> = ADC_CH, see section Summary of all programmable registers (parameters, functions) Full motor current measurement range corresponds to VADC = 4.0 V. Multiplexed output must not be switched during operation! regulated voltage Vref = 1.0 V, external resistor Rref = 22 k must be connected to generate the 45 A reference current. Use Pin Iref to connect Rref only. Analog signal parameters Note (4): Table 8 Revision 1.8, Date 2005-03-17 Page 8 of 35 Data Sheet AS8446 Wake-up system Parameter Low Level Input Voltage High Level Input Voltage Input Hysteresis Table 9 Wake-up system signal parameter Pin type HV AIO Symbol VIL VIH VHYS Min -8 0.6 * Vbat 0.05 * Vbat Max 0.4 * Vbat Vbat 0.1 * Vbat Unit V V V Note VIH - VIL Start up Behavior 14 V Vbat nPORraw (VDDraw) 4.3 V 5.0 V 4.3 V 5.0 V RESET by nPOR possible RESET by watch dog 20 us 4.3 V RESET by nPOR RESET 5.0 V SPI communication possible nPOR (VDD) time is user defined by LIN wake up 300 us VPok (Charge pump enable) 300 us 100 us ... 500 us Mcalib (calibration ready) 200 us not Sleep R17 defined not Registers R1 to R16 defined Failure R18 not defined sleep mode defined (start-up) redefined (start-up) defined by SPI defined by SPI and/or failure detection units measurement unit calibration sleep mode defined (start-up) not defined 14 V wake up Wake-up Charge pump start up driver enable SPI sends 1 to R17 (sleep) wake up t = t1 t2 t t3 system enable (normal work) t4 sleep mode t5 t = t1 + T new system start-up first system start-up (connection of Vbat to the system) Figure 4 Start up and sleep mode behavior of AS8446 (simplified timing) Revision 1.8, Date 2005-03-17 Page 9 of 35 Data Sheet AS8446 Programming Capabilities There are in total 18 registers to program the behavior of the AS8446 via the Three Wire Interface Register No R1<4:0> R2<4:0> R3<2:0> R4<4:0> R5<3:0> R6<1:0> R7<4:0> R8<1:0> R9<2:0> R10<1:0> R11<2:0> R12<2:0> R13<2:0> R14<0:0> R15<3:0> R16<0:0> R17<1:0> R18<7:0> Register Name SRon SRon_stat SRon_min SRoff Sroff_stat Acu_on/off AV_TRIMM AV_RANG_norm OVERC_level AV_RANG_over VBAT_RANG OVER_VOLT UNDER_VOLT VPUMP_MIN ADC_CH WATCH_D SLEEP FAILURE_STAT Meaning EMC parameter 1, rising edge EMC parameter 2, rising edge EMC parameter 3, rising edge EMC parameter 1, falling edge EMC parameter 2, falling edge EMC parameter, rising and falling edge, multiplying factor 1 or 2 Motor current measurement amplification (steps of 1.25%) Motor current measurement amplification, normal measurement channel (large steps) Over current threshold value Motor current measurement amplification, over current measurement channel (large steps) Range of supply voltage (max. battery voltage to measure) Over voltage threshold value Under voltage threshold value Min. pumped voltage (Vpump - Vbat) Selection of one of the analog channel to be connected to pin ADC (AnalogMUX) Switch on or off of watch dog function Switch on or off of sleep mode Failure status register Full descriptions of all registers see below. Table 10 Meaning of the AS 8446 registers. Driver Programming (Slew Rate Regulation Parameters) The Power FET driver is controlled in two different ways: 1. By the digital input PWM (output of the PWM generator of the P) to realize the PWM duty cycle of the motor drive for regulating the motor current, speed or voltage in the closed loop. 2. By the dynamically self-adjusting slew rate regulated switching technology during the rising and falling edges of the motor voltage. There are 6 registers to program the driving parameters in different time intervals of the rising and the falling edge of the motor voltage independently (definition of the time functions of the power FET driver gate currents in wide ranges): Rising edge: registers R1<4:0>, R2<4:0>, R3<2:0> and R6<0> Falling edge: registers R4<4:0>, R5<3:0> and R6<1> These registers can be programmed via the Three-Wire Interface and thus the EMC behavior of the system (motor, power switches, cables) can be adapted and optimized to a particular application. Although the total rising and falling times are very short ( tRISE or tFALL < 150 ns with driver currents to the power FET gate up to 500 mA), the RF emission (EMC) is very low. See also section Summary of all programmable registers (parameters, functions). A detailed description of these programming and EMC optimization will be given in the application manual of the AS8446. Revision 1.8, Date 2005-03-17 Page 10 of 35 Data Sheet AS8446 Rising edge (switch on): Programmable Gate Drive Source Currents (13 bit) Register / timing part of rising edge Programmable range Programmable range Unit Note R6<0> = 1, Acu_on/off min max step R1<4:0> = SRon (Vmotor = 12.7 V) R1<4:0> = SRon (Vmotor = 30.7 V) R2<3:0> = SRon_stat R3<2:0> = SRon_min (Vmotor = -0.5 V) Note (1): Table 11 R6<0> = 0, Acu_on/off min max step 0 0 0.5 10 248 (620) 1 16 80 8 20 0.5 10 mA mA mA mA R2 = 0, 1, 2, ... 15 R3 = 0, 1, 2, ... 7 R1 = 0, 1, 2, ... 31 0 0 1.0 20 496 (1240) 1 32 160 16 40 1.0 20 The total driver current Iout_on must be limited to 500 mA (Iout_on < 500 mA ) in the real application with the given Vmotor_max = Vbat by appropriate programming. Programming of the slew rate parameters (rising edge) Figure 5 Rising edge of the motor voltage before and after the EMC optimization Revision 1.8, Date 2005-03-17 Page 11 of 35 Data Sheet AS8446 Falling edge (switch off): Programmable Gate Drive Sink Currents (10 bit) Register / timing part of falling edge Programmable range Programmable range Unit Note R6<1> = 1, Acu_on/off min max step R4<4:0> = SRoff (Vmotor = 12.7 V) R4<4:0>, SRoff (Vmotor = 30.7 V) R5<3:0>, SRoff_stat Note (1): Table 12 R6<1> = 0, Acu_on/off min max step 0 0 5 248 (620) 1 80 8 20 5 mA mA mA R2 = 0, 1, 2, ... 15 R4 = 0, 1, 2, ... 31 0 0 1.0 496 (1240) 1 32 16 40 1.0 The total driver current Iout_on must be limited to 500 mA (Iout_on < 500 mA ) in the real application with the given Vmotor_max = Vbat by appropriate programming. Programming of the slew rate parameters (falling edge) Figure 6 Falling edge of the motor voltage before and after the EMC optimization IBEE DUT: Ingenieurburo fur industrielle Elektrotechnik/ Elektronik Conditions: Prof. Dr.-Ing. habil. D. Sperling Conducted Emission power supply lines according CISPR 25 Demo board AS8444_TC Load : Ri = 0.4 Ohm, Li = 0.063 mH Detector: Peak V BAT = 13.5 V EMC parameter set 1 (not EMC optimized) EMC parameter set 2 (EMC optimized) 80 70 EMC parameter set 1 60 50 [dBV] (not EMC optimized) 40 30 20 10 0 -10 0.1 1 10 [MHz] EMC parameter set 2 (EMC optimized) 100 1000 Figure 7 Comparison of the EMC measurement results of the same application with two different EMC parameter sets Revision 1.8, Date 2005-03-17 Page 12 of 35 Data Sheet AS8446 Programming of the motor current measurement unit and the over current detection unit The motor current measurement unit operates with an external current measurement resistor Rmeas in the high side motor line. The chip has two measurement amplification channels with separately programmable amplification factors: a) normal motor current measurement, channel 1 AVmeas_norm = VA_current / Vmeas with Vmeas = (VCMP - VCMN), analog output A_current (multiplexed to output ADC) and b) over current measurement with extended measurement range, channel 2 AVmeas_overc = VA_overc / Vmeas, analog output A_overc (multiplexed to output ADC). In general all programming possibilities in table 14 can be used to build up a measurement system in the defined limits. The programming words are sent from the P via the Three-Wire Interface to the AS8446 during start up of the system. The typical value of Vmeas_nom = (VCMP - VCMN)nom is 50 mV, corresponding to 100% of the motor current. In the whole system the analog outputs A_current or A_overc are used by the ADC of the P to regulate and control the system. There is only one exception: The over current detection and protection is realized directly by the over current measurement channel in order to act very fast in case of an over current situation e.g. short circuit of the motor. Figure 8 Programming examples of the current measurement channels Figure 9 Programming examples of the over current detection Figure 8 shows the programming of the normal current measurement channel (red lines, output voltage VCUR) and the over current measurement channel with extended measurement range (blue lines, output voltage VCOVER). The three lines with the parameters AV_TRIMM = 70, 80, 90 indicate the trimming range of the external measurement resistor (+ 12.5 % in steps of 1.25 %). The total range of the normal measurement amplification is AVmeas_norm = 70 to 360 corresponding to input voltages Vmeas_max = 11 mV to 57 mV. The total range of the over current measurement amplification is AVmeas_overc = 17.5 to 90 corresponding to input voltages Vmeas_max = 44 mV to 229 mV. Figure 9 shows an example of the programming of the over current threshold level (generation of the over current signal VPOV, red lines): AVmeas_overc = 20 and OVERC_level = 0.5 V to 4.0 V in steps of 0.5 V. All programming possibilities are given in table 14 below. Revision 1.8, Date 2005-03-17 Page 13 of 35 Data Sheet AS8446 Programming of the motor current measurement and over current detection unit The motor current measurement unit transforms the differential voltage over the measurement resistor at the high side motor line (VCMP - VCMN) = Imotor * Rmeas to the ground related voltage VA_current (channel1) and to the ground related voltage VA_overc (channel2) with a programmable amplification. Definition and programming of the voltage amplifications AVmeas_norm and AVmeas_overc of the motor current measurement unit: a) channel 1: AVmeas_norm = VA_current / (VCMP - VCMN) = AV_TRIMM * AV_RANGE_norm b) channel 2: AVmeas_overc = VA_overc / (VCMP - VCMN) = AV_TRIMM * AV_RANGE_over Register No R7<4:0> Register Name AV_TRIMM Meaning Voltage amplification factor1 of the current measurement unit in small steps (trimming of the external current measurement resistor) for the normal and over current analog measurement output R7 = 0 a AV_TRIMM = 70 R7 = 1 a AV_TRIMM = 71 R7 = 2 a AV_TRIMM = 72 : R7 = 10 a AV_TRIMM = 80 (default value) R7 = 11 a AV_TRIMM = 81 : R7 = 19 a AV_TRIMM = 89 R7 = 20 a AV_TRIMM = 90 R7 > 20 a AV_TRIMM = 90 Voltage amplification factor2 of the normal analog measurement output (A_current) R8 = 0 a AV_RANGE = 1 (default value) R8 = 1 a AV_RANGE = 2 R8 = 2 a AV_RANGE = 3 R8 = 3 a AV_RANGE = 4 Threshold value of the internal over current detection Def.: Vocmax = 4/5 * VDD (typ. Vocstep = (4/5 * VDD) / 8 (typ. R9 = 0 a OVERC_level = Vocmax (typ. R9 = 1 a OVERC_level = Vocmax - Vocstep (typ. R9 = 2 a OVERC_level = Vocmax - 2*Vocstep (typ. R9 = 3 a OVERC_level = Vocmax - 3*Vocstep (typ. : R9 = 7 a OVERC_level = Vocmax - 7*Vocstep (typ. 4.0 0.5 4.0 3.5 3.0 2.5 V) V) V) V) V) V) R8<1:0> AV_RANGE R9<2:0> OVERC_level 0.5 V) R10<1:0> AV_RANGE_over Voltage amplification factor2 of the over current analog measurement output (A_overc) R10 = 0 a AV_RANGE_over = 1 * 1/4 (default value) R10 = 1 a AV_RANGE_over = 2 * 1/4 R10 = 2 a AV_RANGE_over = 3 * 1/4 R10 = 3 a AV_RANGE_over = 4 * 1/4 Remark 1: The maximum of the valid analog output voltage of the outputs A_current and A_overc must be 4.0 V. Remark 2: The total voltage amplification of the current measurement unit is determined by normal current analog output A_current: AVmeas_norm = VA_current / (VCMP - VCMN) = AV_TRIMM * AV_RANGE (default value: 80) over current analog output A_overc: AVmeas_overc = VA_overc / (VCMP - VCMN) = AV_TRIMM * AV_RANGE_over (default value: 20) Revision 1.8, Date 2005-03-17 Page 14 of 35 Data Sheet AS8446 Remark 3: The external current measurement voltage over the measurement resistor Rmeas (VCMP - VCMN) = Imotor * Rmeas where the internal over current detection is switched on can be determined by: (VCMP - VCMN)overc * AV_TRIMM * AV_RANGE_over = OVERC_level (VCMP - VCMN)overc = OVERC_level / (AV_TRIMM * AV_RANGE_over) example: OVERC_level = 4 V, AV_TRIMM = 80, AV_RANGE_over = 1/4 a (VCMP - VCMN)overc = 200 mV Remark 4: Example of the programming of the current measurement / over current detection unit: Step1: Definition of the nominal voltage drop over the external current measurement resistor Rmeas (VCMP - VCMN)nom = Imotornom * Rmeas e.g. (VCMP - VCMN)nom = 50 A * 1 m = 50 mV Step2: Definition of the over current threshold value of (VCMP - VCMN) e.g. (VCMP - VCMN)overc = 100 mV Step3: Determination of the voltage amplification of the normal current measurement channel so that the nominal output voltage VA_current_nom = 4.0 V e.g. AV_TRIMM * AV_RANGE = 80 * 1 a VA_current-nom = 50 mV * 80 = 4.0 V Step4: Determination of the voltage amplification of the over current measurement e.g. AV_TRIMM * AV_RANGE_over = 80 * 1/4 a VA_overc_max = 100mV * 20 = 2.0 V < 4.0 V Step5: Determination of the programming of the internal over current threshold value (OVERC_level) With the formula: (VCMP - VCMN)overc = OVERC_level / (AV_TRIMM * AV_RANGE_over) and all values above: OVERC_level = (VCMP - VCMN)overc * (AV_TRIMM * AV_RANGE_over) = 100 mV * 80 *1/4 = 2.0 V a R9 = 4 Remark 5: The amplifications AVmeas_norm and AVmeas_overc of the current measurement unit can be adapted to the external measurement resistor Rmeas by the programming word AV_TRIMM in steps of 1.25 % in the range of + 12.5% (trimming of Rmeas). Table 13 Programming of the motor current measurement an over current detection unit Revision 1.8, Date 2005-03-17 Page 15 of 35 Data Sheet AS8446 Summary of all programmable registers (parameters, functions) Register / address Internal name Meaning Note Ra Programming of the driver output currents (independent for switch on and switch off) R0<7:0> R1<4:0> SRon Not used Slew rate regulation programming, on switch, voltage VVmo dependent driver output current for positive VVMO voltage SRon = 0, 1, 2, ... 31 VVMO > 0 ISRon = VVmo * Acu_on * SRon * K1 Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit R2<4:0> SRon_stat d4 1 d3 1 d2 1 d1 1 d0 1 start up values Slew rate regulation programming, on switch, constant driver output current SRon_stat = 0, 1, 2, ... 31 ISRon_stat = 2.0 A * (SRon_stat + 1) * Acu_on Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit d4 1 d3 1 d2 1 d1 1 d0 1 start up values R3<2:0> SRon_min Slew rate regulation programming, on switch, voltage VVMO dependent driver output current for negative VVMO voltage SRon_min = 0, 1, 2, ...7 ISRon_min = VVmo * (SRon_min + 1) *Acu_on * K2 VVMO < 0 Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit d2 1 d1 1 d0 1 start up values Revision 1.8, Date 2005-03-17 Page 16 of 35 Data Sheet AS8446 R4<4:0> SRoff Slew rate regulation programming, off switch, voltage VVMO dependent driver input current for positive VVMO voltage SRoff = 0, 1, 2, ... 31 ISRoff = VVmo * Acu_off * SRoff * K3 Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit d4 1 d3 1 d2 1 d1 1 d0 1 start up values R5<3:0> SRoff_stat Slew rate regulation programming, off switch, constant driver input current SRoff_stat = 0, 1, 2, ... 15 ISRoff_stat = 20 A * (SRoff_stat + 1) * Acu_off Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit d3 1 d2 1 d1 1 d0 1 start up values R6<1:0> Acu_on Acu_off Current amplification of the driver for on and off switch R6<0> = 0 a Acu_on = (Iout / Iin)on = 256 R6<0> = 1 a Acu_on = (Iout / Iin)on = 512 R6<1> = 0 a Acu_off = (Iout / Iin)off = 256 R6<1> = 1 a Acu_off = (Iout / Iin)off = 512 Register write by: Three Wire Interface Register read by: Three Wire Interface and FET driver unit Acu_off 0 Acu_on 0 start up values Programming of the motor current measurement and over current detection unit The motor current measurement unit transforms the differential voltage over the measurement resistor (VCMP - VCMN) = Imotor * Rmeas to the ground related voltages VA_current (channel1: normal current measurement channel) and VA_overc (channel2: over current measurement channel) with a programmable amplification. Def. of the voltage amplification of the motor current measurement unit: Voltage amplification of the normal current measurement channel: 1. AVmeas_norm = VA_current / (VCMP - VCMN) = AV_TRIMM * AV_RANGE_norm Voltage amplification of the normal current measurement channel 2. AVmeas_overc = VA_overc / (VCMP - VCMN) = AV_TRIMM * AV_RANGE_over Revision 1.8, Date 2005-03-17 Page 17 of 35 Data Sheet AS8446 R7<4:0> AV_TRIMM R7 = 0 a AV_TRIMM = 70 R7 = 1 a AV_TRIMM = 71 R7 = 2 a AV_TRIMM = 72 : R7 = 10 a AV_TRIMM = 80 (default value) R7 = 11 a AV_TRIMM = 81 : R7 = 19 a AV_TRIMM = 89 R7 = 20 a AV_TRIMM = 90 R7 > 20 a AV_TRIMM = 90 Register write by: Three-Wire Interface Register read by: Three-Wire Interface and current measurement unit d4 0 d3 1 d2 0 d1 1 d0 0 start up values R8<1:0> AV_RANGE_norm R8 = 0 a AV_RANGE-norm = 1 (default value) R8 = 1 a AV_RANGE-norm = 2 R8 = 2 a AV_RANGE-norm = 3 R8 = 3 a AV_RANGE-norm = 4 Register write by: Three-Wire Interface Register read by: Three-Wire Interface and current measurement unit d1 0 d0 0 start up values R9<2:0> OVERC_level Threshold value of the internal over current detection Def.: Vocmax = 4/5 * VDD (typ. 4.0 V) Vocstep = (4/5 * VDD) / 8 (typ. 0.5 V) R9 = 0 a OVERC_level = Vocmax (typ. 4.0 V) R9 = 1 a OVERC_level = Vocmax - Vocstep (typ. 3.5 V) R9 = 2 a OVERC_level = Vocmax - 2*Vocstep (typ. 3.0 V) R9 = 3 a OVERC_level = Vocmax - 3*Vocstep (typ. 2.5 V) : R9 = 7 a OVERC_level = Vocmax - 7*Vocstep (typ. 0.5 V) Register write by: Three-Wire Interface Register read by: Three-Wire Interface and current measurement unit d2 0 d1 1 d0 1 start up values R10<1:0> AV_RANGE_over Voltage amplification factor2 of the over current analogue measurement output (A_overc) R10 = 0 a AV_RANGE_over = 1 * 1/4 (default value) R10 = 1 a AV_RANGE_over = 2 * 1/4 R10 = 2 a AV_RANGE_over = 3 * 1/4 R10 = 3 a AV_RANGE_over = 4 * 1/4 Register write by: Three-Wire Interface Register read by: Three-Wire Interface and current measurement unit d1 0 d0 0 start up values Revision 1.8, Date 2005-03-17 Page 18 of 35 Data Sheet AS8446 Programming of the battery voltage monitor and over / under voltage detection R11<2:0> VBAT_RANGE R11= R11= R11= R11= R11= 0 1 2 3 4 a a a a a VBAT_RANGE VBAT_RANGE VBAT_RANGE VBAT_RANGE VBAT_RANGE = = = = = 5 a Vbat-max = 20 V 8 a Vbat-max = 32 V 10 a Vbat-max = 40 V 15 a Vbat-max = 60 V 20 a Vbat-max = 80 V Register write by: Three-Wire Interface Register read by: Three-Wire Interface and voltage monitor R12<2:0> OVER_VOLT R11= R11= R11= R11= R11= 0 1 2 3 4 a a a a a = = = = = d2 0 d1 1 d0 0 start up values VBAT_RANGE VBAT_RANGE VBAT_RANGE VBAT_RANGE VBAT_RANGE 5 a Vbat-max = 20 V 8 a Vbat-max = 32 V 10 a Vbat-max = 40 V 15 a Vbat-max = 60 V 20 a Vbat-max = 80 V Register write by: Three-Wire Interface Register read by: Three-Wire Interface and voltage monitor R13<2:0> UNDER_VOLT d2 1 d1 1 d0 1 start up values Step of UNDER_VOLT = 0.25 V * VBAT_RANGE UNDER_VOLT = 0.25 V * VBAT_RANGE * (R13 + 1) Start up value: UNDER_VOLT = 7.5 V Register write by: Three-Wire Interface Register read by: Three-Wire Interface and voltage monitor d2 0 d1 0 d0 0 start up values Programming of the charge pump voltages R14<0:0> VPUMP_MIN R14 = 0 a VPUMP_MIN = 4.0 V R14 = 1 a VPUMP_MIN = 6.0 V Register write by: Three-Wire Interface Register read by: Three-Wire Interface and charge pump d0 0 start up values Revision 1.8, Date 2005-03-17 Page 19 of 35 Data Sheet AS8446 Programming of the analog MUX R15<3:0> ADC_CH R15 = 0 a A_current R15 = 1 a A_overc R15 = 2 a Vbat_mon R15 = 3 a TP The following signals can purposes: R15 = 4 a Vtemp R15 = 5 a PVover R15 = 6 a PVunder R15 = 7 a PTover_in R15 = 8 a PTover_ex (normal current measurement channel) (over current measurement channel) (Vbat measurement channel) (temperature measurement channel) be given at the ADC output for chip test (temperature voltage of the internal sensor) (Over voltage Vbat signal) (Under voltage Vbat signal) (Over temperature signal, internal) (Over temperature signal, external) Register write by: Three-Wire Interface Register read by: Three-Wire Interface and analog MUX Note: d3 0 d2 0 d1 0 d0 0 start up values Do not switch the analog MUX during operation! Programming of the watch dog R16<0:0> WATCH_D R16 = 0 a watch dog is off (watch dog not used) R16 =1 a watch dog is on (watch dog used) Register write by: Three-Wire Interface Register read by: Three-Wire Interface and watch dog d0 0 start up values Programming of the sleep mode R17<0:0> SLEEP R17 = 0 a no sleep mode (normal operation) R17 = 1 a sleep mode (power down) Register reset to low by the Wake-up Interface. Wake-up = low (high / low edge) a R17<0:0> set to low d0 1 start up values Revision 1.8, Date 2005-03-17 Page 20 of 35 Data Sheet AS8446 Failure Registers and Test Mode Register (on chip temperature detection) R18<7:0> FAILURE_STAT R18<0> R18<1> R18<2> R18<3> R18<4> R18<5> R18<6> a a a a a a a Poverc PVover PVunder PTover_in PTover_ex VDDover VDDunder (bit 0 contains the over current status) (bit 1 contains the over voltage status of Vbat) (bit 2 contains the under voltage status of Vbat) (bit 3 contains the on chip over temperature status) (bit 4 contains the external over temperature status) (bit 5 contains the over voltage status of VDD, 5 V) (bit 6 contains the under voltage status of VDD, 5 V) R18<7> = 0 a R18<7> = 1 a band gap Voltage is the reference voltage for the on chip over temperature detection (normal function) the voltage at pin TP is the reference voltage for the on chip over temperature detection (test mode) set and reset by Three-Wire Interface and only set by corresponding failure detection units (Three Wire-Interface has write priority) read by Three-Wire Interface and corresponding logic write by Three-Wire Interface only read by Three-Wire Interface and corresponding analog switch PTover_in 0 PVunder 0 PVover 0 Poverc 0 start up values Registers R18<6:0> Register R18<6:0> Register R18<7> Register R18<7> TEMP_TEST 0 Table 14 VDDunder 0 VDDover 0 PTover_ex 0 Summary of the programming capabilities of the AS 8446 Revision 1.8, Date 2005-03-17 Page 21 of 35 Data Sheet AS8446 Three -Wire P-Interface Data transfer from the microprocessor or PC to the AS8446 and vice versa is accomplished by means of Three-Wire Interface. The Three-Wire Interface of the AS8446 acts generally in slave mode. The master in the whole regulator board is either the controlling P (normal regulator module in volume production) or a PC (development or field programming mode e.g. to realize the EMC optimization). All registers (see section Summary of all programmable registers (parameters, functions)) can be written and read by the Three-Wire Interface. Pin DATAout is high ohmic if the Three-Wire Interface chip select signal CS is not active (high). During an over voltage situation the write access to the Three-Wire Interface is blocked. Physical Interface Supported modes, and bit order are shown in Figure 10 and Figure 11. The DATAin signal must be valid with the rising edge of the clock Clk, the DATAout is valid with the falling edge of the clock Clk. The clock frequency should be as low as useful in the particular application. It is recommended not to use a clock frequency fclk higher than 10 MHz. The MSB is always transmitted / received first. CS Clk > 30 us first frame > 0.1 us > 30 us next frame LSB MSB HEADER LSB MSB DATA DATAin DATAout Figure 10 Physical Interface of Three-Wire Interface in write mode CS Clk > 30 us first frame > 30 us next frame MSB HEADER LSB MSB DATA DATAin LSB DATAout Figure 11 Physical Interface of Three-Wire Interface in read mode Revision 1.8, Date 2005-03-17 Page 22 of 35 Data Sheet AS8446 Communication Protocol The Three-Wire Interface -interface acts as communication interface between the P or PC and the registers within the AS8446. For efficient register access, a protocol has been defined with the following features: Purely master-slave protocol with P or PC as master Two different frames: One read and one write frame Frame is delimited by the status of CS (CS = frame delimiter or chip select signal), one frame consists of 16 Bits (header byte and data byte). Special remark for interface lock condition: If a frame does not consist of 16 bits (can be caused e.g. by spiking, noise or interrupt), the interface will be locked. In order to leave this lock situation CS = high and one or several clock pulses must be set. Setting CS = high alone will not be sufficient. Referring to Figure 10 and Figure 11, a Clk pulse with CS = high must be set in order to reset the interface and to ensure a safe communication. Data Fields HEADER H MSB R/W H A4 A3 A2 A1 LSB A0 A4, A3, A2, A1, A0: Address A (Register address to read or to write) R/W = MSB, A0 = LSB. R/W: Read or Write R/W =0: Read (Data are read/transmitted from the AS8446 via the DATAout pin.) R/W =1: Write (Data are write/transmitted from the P or PC to the AS8446 via the DATAin pin.) DATA D MSB D7 D D6 D5 D4 D3 D2 D1 LSB D0 D7...D0: Data (Denotes the data of the register addressed. D7=MSB, D0=LSB) Note: To ensure a correct register setting the use of P based verification (Write, Read-Back, Verify) is mandatory. Revision 1.8, Date 2005-03-17 Page 23 of 35 Data Sheet AS8446 Electrical Parameters and Functionality of the Subblocks All parameters are valid in the temperature range Tamb = -40 o C to +125 o C if not otherwise mentioned. 5V Regulator PARAMETER Regulated Output Voltage Load Current at VDD Under voltage detection threshold Over voltage detection threshold SYMBOL VDD IOUT VDDunder VDDover 4.3 5.6 MIN 4.8 TYP 5.0 MAX 5.15 40 UNIT V mA V V NOTE (1) (2), (3), (4) Note (1): For use of the internal voltage regulator the Pins VDD and VDDctrl must be connected. An external capacitor of 4.7F to 10F needs to be connected at the VDD pin. Note (2): Valid for Vbat 6.5V; for 6.0V Vbat < 6.5V the load current is limited to 2.5mA. Note (3): There is also the possibility to use an external regulator (Bipolar transistor). It is up to the user to select the suitable external components. Note (4): The max. power dissipation on chip must be respected (estimation: Pchip_vdd = ((Vbatmax - 5 V ) * Ivdd_ex + Vbat * Ivdd_in) < 400 mW ) Design Example V BAT V DDctrl 100 R T1 220 nF (Ceramic) V DD C VDD 100 F / 16V 47 nF T1... Philips NPN medium power transistor BCX 56 CVDD... Panasonic FK-series 100F / 16V Figure 12: Design example for operation of external voltage regulator Power on Reset 5 4 3 2 1 1 2 3 4 5 5 4 3 2 1 0 Figure 13 Transfer characteristic of PORn circuitry Revision 1.8, Date 2005-03-17 Page 24 of 35 Data Sheet AS8446 PARAMETER Off threshold for Reset generation Hysteresis of Reset signal SYMBOL Voff_PORS Hyst_PORS MIN 2.1 0.1 TYP 3.5 MAX 4.5 0.8 UNIT V V NOTE Ramp up Sleep / wake up system The whole IC is put in sleep mode (power down mode) by the control signal SLEEP set via the Three Wire Interface (SLEEP = high, content register R17). The whole start up and sleep mode behavior is shown in figure 4. In sleep mode the following actions are done: the power FET driver output OUT is hold at low (VSS) the oscillator, the charge pump and all other blocks are put in a high ohmic status the 5 V regulator is switched off (no external supply at pin VDD, this way all devices on the motor regulator board supplied by VDD, e.g. the P and the external temperature sensor, are powered down) a raw internal 5 V supply VDDraw is generated to supply the wake up system and the whole logic block the total current consumption of the IC is less than 90 A During sleep mode the Wake-up Pin must be at high level (VBAT). Applying a "low"-pulse on the wake-up pin will wake up the IC. PARAMETER Current Consumption in Sleep Mode (Tamb = -40 o C to 125 o C) Current Consumption in Sleep Mode (1) (Tamb = -40 o C to 27 o C) SYMBOL Ivbat_pd Ivbat_pd27 MIN TYP MAX 90 (50) UNIT A A NOTE R17<0> = 1 (SLEEP = high) Note (1): only as information. Will not be tested. Reference Current Generator The reference current generator uses a bandgap based 1 V reference voltage to generate a buffered 1 V voltage reference at pin Iref. A 22 k external resistor must be used to generate the 45 A current reference. PARAMETER Voltage at pin Iref SYMBOL Vref MIN 0.95 TYP 1.0 MAX 1.05 UNIT V NOTE High Side Power FET Driver / Slew Rate Regulation The supply voltage of this driver is about 10 V higher than the Vbat (n-channel power FET to drive) and is delivered by the on chip charge pump at pin Vpump. The Power FET driver is controlled in two different ways: First by the digital output of the PWM generator of the P to realizing a certain duty cycle of the motor drive and so to regulate the motor current, voltage or speed in a closed loop. The driver output OUT is set to low (the motor is switched off) independently of the PWM signal under the following conditions: * over current condition: The over current signal Poverc is set to high by the over (Poverc = high) * * under voltage condition of Vbat: (PVunder = high) over voltage condition of Vbat: (PVover = high ) current detection unit and reset to low via the Three Wire Interface The under voltage signal PVunder is set and reset by the voltage monitor. The over voltage signal PVover is set and reset by the voltage monitor. Revision 1.8, Date 2005-03-17 Page 25 of 35 Data Sheet AS8446 * charge pump voltage Vpump - Vbat is too low: The charge pump OK signal VPok is set and reset by the charge pump (VPok = low ) monitor. The threshold values of these parameters are programmable (see section Summary of all programmable registers (parameters, functions)). * the calibration of the motor current measurement unit is not yet finished: Mcalib = low. The motor current must be zero respectively the voltage (VCMP - VCMN ) must be zero during the calibration. This calibration is done after the start up of the system including the ready signal of the charge pump: power on reset signal nPOR and Vpok = high starts the calibration. The calibration procedure needs about 200 s (see figure 4). Summary of logic driver function: OUT = PWM and /Poverc and /PVunder and /PVover and VPok and Mcalib Second by the analog motor voltage to regulate the slew rate during the rising and falling edge of the motor voltage (EMC conform technology). This slew rate control respectively regulation is executed by a feedback of the motor voltage Vmotor available at the pin Vmo. The characteristics (parameters) of this slew rate regulation can be programmed via the Three-Wire Interface independently for the falling and rising edge of the motor voltage and can therefore be adapted to a specific application (motor and its environment). This programming of the output current characteristics (gate current of the external power FET) in both directions is shown in section Summary of all programmable registers (parameters, functions). PARAMETER SYMBOL MIN -50% TYP MAX +50% UNIT NOTE Iout_on = ISRon-stat + ISRon + ISRon_min The relative tolerances between adjacent programming steps of the driver current are less than 10%. Iout_off = ISRoff-stat + ISRoff The relative tolerances between adjacent programming steps of the driver current are less than 10%. Tolerances of driver IOUTon output current (pin OUT), sourcing Tolerances of driver IOUToff output current (pin OUT), sinking - -50% +50% max. pulse duration = 1s @ 20 kHz or max. external charge to load: 250 nC @ 20 kHz valid for IOUT = 5 mA ... 500 mA and Vbat = 12 V , Vpump = 22 V - Programmable by the registers R1 to R6 Revision 1.8, Date 2005-03-17 Page 26 of 35 Data Sheet AS8446 Charge Pump and internal Oscillator The charge pump is a one-stage pump that generates a pumped voltage Vpump about 10 V higher than the supply voltage Vbat for Vbat > 13.5 V. It uses two external capacitors only, the capacitor Cp12 as the switched capacitor and Cp0 as the storage capacitor. The pumped voltage (Vpump - Vbat) is monitored to detect over or under voltages (protection of the power FET gate): (Vpump - Vbat) = 10 V to 12 V : Normal voltage regulation of the charge pump (Vpump - Vbat) < (Vpump - Vbat)low : The digital signal VPok is indicating this under voltage and disabling the power FET driver. The threshold value (Vpump - Vbat)low can be programmed to be 6 V or 4 V (VPUMP_MIN). PARAMETER Pumped voltage Pumped voltage Pumped voltage Under voltage threshold (VPUMP_MIN = 1) Under voltage threshold (VPUMP_MIN = 0) regulated voltage threshold frequency SYMBOL Vpump - Vbat Vpump - Vbat Vpump - Vbat (Vpump - Vbat)low (Vpump - Vbat)low (Vpump - Vbat)high fpump MIN 10 4.0 4.0 5.4 3.4 10 40 6.0 4.0 10.5 50 6.6 4.6 12 70 TYP 10.5 5.0 MAX 12 UNIT V V V V V V kHz NOTE Vbat = 13.5 V, Iload = 5 mA Vbat = 6.5 V, Iload = 2.5 mA 6.0V Vbat < 6.5V (low-Batterymode), Iload = 250A falling (Vpok) falling (Vpok) rising Motor Current Measurement Unit / Over Current Detection The motor current measurement unit functions with an external current measurement resistor Rmeas in the high side motor line. The chip has two measurement amplification channels with separately programmable amplification factors AVmeas_normal = VA_current / (VCMp - VCMn) (analogue output A_current) and AVmeas_over = VA_overc / (VCMp - VCMn) (analogue output A_overc). The maximal valid nominal analogue output voltage level VA_current and VA_overc of theses channels is 4.0 V (100% value of the output voltage VA_current (nominal value). In general, all programming possibilities can be used to build up a measurement system within the defined limits. It is recommended to use a nominal differential voltage (VCMp - VCMn) > 50 mV to avoid larger tolerances of the amplification factor caused by offset. The programming of theses two amplification channels is usually realized in a way that the measurement range of the over current measurement channel is wider than the normal current measurement channel. In the whole system the analogue outputs A_current and A_overc are used via an ADC in the controlling P to regulate and control the system. There is one exception only: The over current detection and protection is realized directly by the over current measurement channel to be able to act very fast in case of an over current situation (short circuit). The measurement unit contains a low pass filter to prevent wrong measurement if short transients of the measurement input voltage occurs (cut-off frequency about 500 kHz). The motor current measurement unit is endowed with an auto calibration procedure for the offset voltage. The motor current respectively the measurement voltage (Vcmp - Vcmn) must be zero during this calibration. This calibration is done after the start up of the system including the ready signal of the charge pump: power on reset signal nPOR and Vpok = high starts the calibration. The calibration procedure needs about 200 s. Revision 1.8, Date 2005-03-17 Page 27 of 35 Data Sheet AS8446 a) Motor current measurement (normal current amplification channel: ACMV_normal , programmed by AV_RANGE_norm (Register R8<1:0>) and AV_TRIMM (Register R7<4:0>) The nominal measurement differential voltage Vmeas_nom (corresponding to 100% of the nominal motor current) Vmeas_nom = (VCMp - VCMn)nom = Imotor_nom * Rmeas must be fixed by the value of Rmeas . So the value of this measurement resistor is given by Rmeas = (VCMp - VCMn)nom / Imotor_nom . The voltage amplification of this motor current measurement unit AVmeas_normal = VA_current / (VCMp - VCMn) is programmable in the range AV_RANGE_norm * AV_TRIMM = (1, 2, 3, 4) * (70, 71, ... 89, 90) Examples: AV_RANGE_norm = 1: ACMV_normal = 70, 71, 72, ... , 80, ... , 89, 90 AV_RANGE_norm = 4: ACMV_normal = 280, 284, 288, ..., 320, ... , 360 (The programming values of AV_RANGE_norm >1 are intended for a measurement of low currents with a higher digital resolution, but in this cases the tolerances of the amplification factor is high due to the remaining offset of the measurement amplifier.) This way the analog output value VA_current of the current measurement unit can be adapted to the external measurement resistor Rmeas (trimming of this resistor in the range + 12.5%). The nominal (respectively 100%) voltage of the measurement unit VA_current (this is the nominal input voltage of the ADC on the P) must be 4.0 V. b) Over current detection and protection (over current amplification channel ACMV_over) The over current amplification channel uses the same input voltage Vmeas = (VCMp - VCMn) as the normal current amplification channel. The voltage amplification of this over current measurement channel ACMV_over = VA_overc / (VCMp - VCMn) is programmable by AV_RANGE_over (Register R10<1:0>) and AV_TRIMM (Register R7<4:0>) in the range ACMV_over = AV_RANGE_over * AV_TRIMM = (1/4, 2/4, 3/4, 4/4) * (70, 71, ... 89, 90) Revision 1.8, Date 2005-03-17 Page 28 of 35 Data Sheet AS8446 Examples: AV_RANGE_over = 1/4: ACMV_over = 17.5, 17.75, 18, ... , 20, ... , 22.25 , 22.5 AV_RANGE_over = 4/4: ACMV_over = 70, 71, 72, ..., 80, ... , 89, 90 The adjustment (trimming) of the measurement resistor Rmeas is realized by the same programming parameter AV_TRIMM (+ 12.5%) like in a). The maximal output voltage of the over current amplification channel VA_overc (this is the nominal input voltage of the ADC on the P) must be 4.0 V. The threshold value of the over current detection can be programmed by the programming parameters OVERC_level (in conjunction with AV_RANGE_over and AV_TRIMM) in the following way. The voltage over the external measurement resistor where the over current situation is detected (Vmeas_over) is given by: with OVERC_level = 0.5 V, 1.0 V, 1.5 V, ... 4.0 V Vmeas_over = OVERC_level / (AV_TRIMM * AV_RANGE_over) See also section Summary of all programmable registers (parameters, functions) for the programming of the parameters above. PARAMETER Tolerance of voltage amplification, normal current measurement channel 1) Tolerance of voltage amplification, over current measurement channel 1) Tolerance of linearity ACMV_normal Tolerance of linearity ACMV_overc Tolerance of over current thresholds Tolerance of over current thresholds Tolerance of over current thresholds Cut off frequency Note (1): SYMBOL ACMV_normal MIN -6 - 10 - 20 - 20 ACMV_over -6 -6 -6 -6 lincurrent linoverc overclevel overclevel overclevel fcut-off -3 -3 - 10 - 20 - 20 400 MAX +6 + 10 + 20 + 20 +6 +6 +6 +6 +3 +3 + 10 + 10 + 20 800 UNIT % % % % % % % % % % % % % kHz NOTE (Programming, nominal amplification) Vmeas = 50 mV, R8 = 0 a 80 Vmeas = 25 mV, R8 = 1 a 160 Vmeas = 16.67mV, R8 = 2 a 240 Vmeas = 12.5 mV, R8 = 3 a 360 Vmeas = 200 mV, R10 = 0 a 20 Vmeas = 100 mV, R10 = 1 a 40 Vmeas = 60.6 mV, R10 = 2 a 60 Vmeas = 50 mV, R10 = 3 a 80 ((VA_current / Vmeas_nom ) - ACMV_normal ) / ACMV_normal ((VA_overc / Vmeas_nom ) - ACMV_overc ) / ACMV_overc R10 = 0, R9 3, Tamb > 25 o C R10 = 0, R9 3, Tamb = -40 o C R10 = 0, R9 > 3, Tamb = (-40 to 125) o C The offset voltage of the current measurement unit at calibration temperature Vmeas_offset is < 1.5 mV (typical: 0.5 mV), the maximal offset temperature drift is + 20 V / K. Revision 1.8, Date 2005-03-17 Page 29 of 35 Data Sheet AS8446 Battery Voltage Monitor and Over / Under Voltage Detection The Battery voltage monitor has to deliver an analog voltage Vbat_mon in the 5V range which is proportional to the high voltage supply Vbat (normally VDDH = Vbat). The measurement range of the supply voltage Vbat is programmable via the register R11<2:0> to adapt the AS8446 to different application supply voltages. Programming of the MEASUREMENT RANGE of Vbat (programmed by register R11<2:0> a VBAT_RANGE) PARAMETER Programmable Measurement Voltage Ranges of Vbat Note (1): Note (2): Programming Register R11 R11= 0 a VBAT_RANGE = 5 R11= 1 a VBAT_RANGE = 8 R11= 2 a VBAT_RANGE = 10 R11= 3 a VBAT_RANGE = 15 R11= 4 a VBAT_RANGE = 20 SYMBOL Vbatmax1 Vbatmax2 Vbatmax3 Vbatmax4 Vbatmax5 MIN MAX 20 32 40 60 80 UNIT V V V V V NOTE (1) The programmable value of VBAT_RANGE determines the max. value of Vbat measurable by the voltage monitor (condition: Vbat / VBAT_RANGE < 4 V). VBAT must not exceed the specified abs. Max. ratings (see Table 3) SYMBOL VBAT_RANGE Vovervolt Vundervolt MIN -6 -10 -10 MAX +6 +10 +10 UNIT % % % NOTE PARAMETER Tolerance of the division factor Tolerance of the programmed over voltage threshold Tolerance of the programmed ounder voltage threshold a) Programming of the OVER VOLTAGE detection level of Vbat (programmed by register R12<2:0> a OVER_VOLT and R11<2:0> a VBAT_RANGE) Remark: The maximum over voltage limit of Vbat for safe functionality of AS8446 is limited to Vbat < 30 V and must be respected by appropriate programming. Programmable steps of OVER_VOLT = 0.25 V * VBAT_RANGE = (1.25 or 2.0 or 2.5 or 3.75 or 5.0 ) V OVER_VOLT = 0.25 V * VBAT_RANGE * (R12 + 9) = 11.25 V ... 80 V During an over voltage situation the write access to the Three Wire Interface is blocked and the driver is switched off. b) Programming of the UNDER VOLTAGE detection level of Vbat (programmed by register R13<2:0> a UNDER_VOLT and R11<2:0> a VBAT_RANGE) Remark: The minimium Vbat for full functionality of AS8446 is limited to Vbat > 6.5 V (except for Low-batterymode reduced functionality is still given between 6V and 6.5V, see Table 4 Operating Conditions). Programmable steps of UNDER_VOLT = 0.25 V * VBAT_RANGE = (1.25 or 2.0 or 2.5 or 3.75 or 5.0 ) V UNDER_VOLT = 0.25 V * VBAT_RANGE * (R13 + 1) = 1.25 V ... 40 V Revision 1.8, Date 2005-03-17 Page 30 of 35 Data Sheet AS8446 Over Temperature Detection On Chip Over Temperature Detection The on chip temperature detection sets the signal PTover_in high if the chip temperature climbs above the specified level. This over temperature detection has a hysteresis of about 20 C. PARAMETER Recovery Temperature Shutdown Temperature On chip temperature voltage threshold voltage of the on chip over temperature comparator Hysteresis of the over temperature comparator SYMBOL Trecovery Tshutdpwn VTEMP VOTI VOTIHYST MIN +130 +150 1 0.8 30 TYP +140 +160 MAX +150 +170 1.4 1 50 UNIT C C V V mV NOTE Information Parameter Information Parameter TON_CHIP = 27 C Information Parameter Information Parameter External Over Temperature Detection The over temperature detection is realized with an external temperature sensor (e.g. NTC). The threshold value of the voltage at pin TP is defined to Vth_TP = 0.5* VDD (typical 2.5 V) and has a hysteresis. PARAMETER Over Temperature threshold value SYMBOL Vth_TP MIN TYP MAX VDD/2 + 0.05 70 UNIT V mV NOTE VDD/2 - 0.05 Negative Hysteresis Vth_TP_HYS_N 30 The over temperature signal PTover_ex is defined in the following way: PTover_ex = high if VIN < Vth_TP (over temperature) PTover_ex = low if VIN > Vth_TP (no over temperature) Analog MUX and Analog Output Buffer The following analog measurement channels and digital signals are output via an analog MUX and an analog buffer to the pin ADC, the MUX is controlled by register R15<3:0> Analog MUX function PARAMETER A_current A_overc Vbat_mon TP Vtemp PVover PVunder PTover_ex PTover_in SYMBOL Normal motor current measurement channel Motor over current measurement channel Battery voltage monitoring Temperature sensor analog value Temperature voltage Over voltage signal Under voltage signal Over temperature signal, extern Over temperature signal, intern R15 = 0 R15 = 1 R15 = 2 R15 = 3 R15 = 4 R15 = 5 R15 = 6 R15 = 7 R15 = 8 TYP NOTE Used in normal application to control / regulate the system Used for test purposes only Revision 1.8, Date 2005-03-17 Page 31 of 35 Data Sheet AS8446 Analog buffer characterization PARAMETER Input/Output voltage range Offset voltage Slew rate Note (1): CLoad = 20 pF SYMBOL VIO Voffset SRbuffer 1.0 MIN 0.0 TYP MAX 4.0 80 V mV V/s (1) UNIT NOTE Failure Feedback Signal There are two different ways to detect failures in the whole regulator system: * System failures detected directly on chip (e.g. over current, under voltage, ...) and indicated by the appropriate failure signal (e.g. Poverc, PVunder, ..., respectively FAIL) System failures detected by software of the controlling P via the monitoring of the motor current, motor speed, battery voltage, temperature and duty cycle of the PWM signal (e.g. motor failures like blocked motor, open wires, ...). This part of system failures must be defined by the motor and system know how of the customer. The following system failures are detected directly on the AS8446 chip: 1. Over current of the motor (signal: Poverc) 2. Under voltage of the battery voltage Vbat (signal: PVunder) 3. Over voltage of the battery voltage Vbat (signal: PVover) 4. Over temperature of external temperature (signal: PTover_ex) 5. Over temperature of on chip temperature (signal: PTover_in) 6. Under voltage of VDD (5 V) (signal: VDDunder) 7. Over voltage of VDD (5 V) (signal: VDDover) All these seven failures are stored in register R18 and can be read by the controlling P via the Three Wire Interface. A failure signal FAIL is created by OR conjunction of these failures and put to the pin FAIL (can be used as an interrupt signal for the P to start a read access via the Three Wire Interface to the failure register R18): FAIL = Poverc or PVunder or PVover or PTover_ex or PTover_in or VDDunder or VDDover or TEMP_TEST The first three failures (over current, over and under voltage) are used to switch off the driver output OUT immediately by on chip hardware, the two temperature failure and the VDD over / under voltage failure are only detected and can be treated by software of the P. The signal TEMP_TEST is only used for test purposes and must be set low in the normal application. If there is a wrong value (high) of TEMP_TEST during the normal application the FAIL signal is set and must be reset via the Three Wire Interface. * Wake-up System (Pin Wake-up) PARAMETER SYMBOL VIL VIH VHYS IPU MIN -8 0.6 VBAT 0.05 VBAT -400 TYP MAX 0.4 VBAT VBAT 0.1 VBAT 5 UNIT V V V A VIH - VIL > 30 k internal pull- up @ VIH = 0.7 VBAT NOTE DC Characteristics Low Level Input Voltage High Level Input Voltage Input Hysteresis Pull- up Current on Input Watch Dog and RESET The watch dog can be used to supervise the function of the controlling P. In cases where this supervising is not necessary, the watch dog is switched off via the Three Wire Interface by sending a zero to R16<0:0>. The default value after the start up of the system is R16<0:0> = 0 (watch dog is not active). Revision 1.8, Date 2005-03-17 Page 32 of 35 Data Sheet AS8446 The trigger of the watch dog is done by the high / low edge of the external signal WD (start of the counter). The output signal of the watch dog WDout goes high if the watch dog time is over. The output signal of the watch dog WDout or the nPOR are generate the low active signal RESET (used for external P only): if nPOR = low or (WDout = high) and R16<0> = high) a RESET = low PARAMETER time out of the watch dog RESET pulse duration SYMBOL Twatch Twatch_d MIN 110 14 TYP 160 20 MAX 190 25 UNIT ms s NOTE Package Drawing and Marking E H 12 3 TOP VIEW D A1 A e SIDE VIEW b L END VIEW Figure 14 Physical Dimensions (SOIC28) of AS 8446 Physical Dimensions SOIC28 (millimeters) D MIN. NOM. MAX. 17.81 17.93 18.06 E 7.42 7.52 7.59 H 10.16 10.31 10.41 A 2.46 2.56 2.64 A1 0.127 0.22 0.29 e 1.27 BSC b 0.35 0.41 0.48 L 0.61 0.81 1.02 0 5 8 Revision 1.8, Date 2005-03-17 Page 33 of 35 Data Sheet AS8446 Physical Dimensions SOIC28 (inches) D MIN. NOM. MAX. Table 15 E .292 .296 .299 H .400 .406 .410 A .097 .101 .104 A1 .0050 .0090 .0115 e .050 BSC b .014 .016 .019 L .024 .032 .040 0 5 8 .701 .706 .711 Physical Dimensions of AS 8446 Figure 15 Marking of AS 8446 Marking: YYWWIZZ YY: WW: I: ZZ: Manufacturing Year Manufacturing Week Plant Identifier Letters Of Free Choice AY W W I Z Z Figure 16 PB-free Marking of AS 8446 Marking: AYWWIZZ A: Y: WW: I: ZZ: Pb-Free Identifier Last Digit of Manufacturing Year Manufacturing Week Plant Identifier Traceability Code Revision 1.8, Date 2005-03-17 Page 34 of 35 Data Sheet AS8446 Contact austriamicrosystems AG A 8141 Schloss Premstatten, Austria T. +43 (0) 3136 500 0 F. +43 (0) 3136 525 01 info@austriamicrosystems.com Copyright Copyright (c) 2003 austriamicrosystems. Trademarks registered (R). All rights reserved. The material herein may not be reproduced, adapted, merged, translated, stored, or used without the prior written consent of the copyright owner. To the best of its knowledge, austriamicrosystems asserts that the information contained in this publication is accurate and correct. Revision 1.8, Date 2005-03-17 Page 35 of 35 |
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