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| 1. general description the PCA9508 is a cmos integrated circuit that supports hot-swap with zero offset and provides level shifting between low voltage (down to 0.9 v) and higher voltage (2.7 v to 5.5 v) for i 2 c-bus or smbus applications. while retaining all the operating modes and features of the i 2 c-bus system during the level shifts, it also permits extension of the i 2 c-bus by providing bidirectional buffering for both the data (sda) and the clock (scl) lines, thus enabling two buses of 400 pf. using the PCA9508 enables the system designer to isolate two halves of a bus for both voltage and capacitance, and perform hot-swap and voltage level translation. furthermore, the dual supply pins can be powered up in any sequence; when any of the supply pins are unpowered, the 5 v tolerant i/o are high-impedance. the hot swap feature allows an i/o card to be inserted into a live backplane without corrupting the data and clock buses. control circuitry prevents the backplane from being connected to the card until a stop command or bus idle occurs on the backplane without bus contention on the card. zero offset output voltage allows multiple PCA9508s to be put in series and still maintains an excellent noise margin. PCA9508 has b side and a side bus drivers. the 2.7 v to 5.5 v bus b side drivers behave much like the drivers on the pca9515a device, while the adjustable voltage bus a side drivers drive more current and incur no static offset voltage. this results in a low on the b side translating into a nearly 0 v low on the a side. the static offset design of the b side PCA9508 i/o drivers prevents them from being connected to another device that has a rise time accelerator including the pca9510/a, pca9511/a, pca9512/a, pca9513/a, or pca9514/a or a static offset voltage including the pca9507 (b side), PCA9508 (b side), pca9509 (a side), pca9515/a, pca9516a, pca9517/a (b side), pca9518, pca9519 (a side), or p82b96/pca9600 (sx/sy side). the a side of two or more PCA9508s can be connected together, however, to allow a star topology with the a side on the common bus, and the a side can be connected directly to any other buffer with static or dynamic offset voltage. multiple PCA9508s can be connected in series, a side to b side, with no build-up in offset voltage with only time-of-?ight delays to consider. the PCA9508 drivers are not enabled unless the bus is idle, v cc(a) is above 0.8 v and v cc(b) is above 2.5 v. the en pin can also be used to turn the drivers on and off under system control. caution should be observed to only change the state of the enable pin when the bus is idle. the output pull-down on the b side internal buffer low is set for approximately 0.5 v, while the input threshold of the internal buffer is set about 70 mv lower (0.43 v). when the b side i/o is driven low internally, the low is not recognized as a low by the input. PCA9508 hot swappable level translating i 2 c-bus repeater rev. 01 28 april 2008 product data sheet
PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 2 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater this prevents a lock-up condition from occurring. the output pull-down on the a side drives a hard low and the input level is set at 0.5v cc(a) to accommodate the need for a lower low level in systems where the low voltage side supply voltage is as low as 0.9 v. t ab le 1 shows the comparison between PCA9508 and i 2 c-bus repeaters. [1] pca9517a is the high esd (6.5 kv hbm and 550 v mm) drop-in replacement for pca9517. 2. features n 2 channel, bidirectional buffer isolates capacitance and allows 400 pf on either side of the device n supports offset-free hot-swap with idle/stop detect circuitry n voltage level translation from 0.9 v to 5.5 v and from 2.7 v to 5.5 v n footprint and functional replacement for pca9515, pca9515a, pca9517 and pca9517a n i 2 c-bus and smbus compatible n active high repeater enable input n static level offset on b side n open-drain input/outputs n lock-up free operation n supports arbitration and clock stretching across the repeater n accommodates standard-mode and fast-mode i 2 c-bus devices and multiple masters n powered-off high-impedance i 2 c-bus pins n a side operating supply voltage range of 0.9 v to 5.5 v n b side operating supply voltage range of 2.7 v to 5.5 v n 5 v tolerant i 2 c-bus and enable pins n 0 hz to 400 khz clock frequency (the maximum system operating frequency may be less than 400 khz because of the delays added by the repeater). n esd protection exceeds 6000 v hbm per jesd22-a114, 450 v mm per jesd22-a115, and 1000 v cdm per jesd22-c101 n latch-up testing is done to jedec standard jesd78 which exceeds 100 ma n packages offered: so8 and tssop8 table 1. PCA9508 and i 2 c-bus repeaters comparison feature pca9507 PCA9508 pca9509 pca9517a [1] pca9519 v cc(a) range (v) 2.7 to 5.5 0.9 to 5.5 1.1 to v cc(b) - 1 0.9 to 5.5 1.1 to v cc(b) - 1 v cc(b) range (v) 2.7 to 5.5 2.7 to 5.5 3.0 to 5.5 2.7 to 5.5 3.0 to 5.5 rise time accelerator yes - - - - idle/stop detect for hot-swap - yes - - - normal i/o a side a side b side a side b side static level offset b side b side a side b side a side PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 3 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 3. ordering information [1] also known as msop8. 4. functional diagram table 2. ordering information t amb = - 40 c to +85 c. type number topside mark package name description version PCA9508d PCA9508 so8 plastic small outline package; 8 leads; body width 3.9 mm sot96-1 PCA9508dp 9508 tssop8 [1] plastic thin shrink small outline package; 8 leads; body width 3 mm sot505-1 fig 1. functional diagram of PCA9508 002aac651 0.5 pf rd s qb uvlo 20 pf 0.55v cc / 0.45v cc 0.5 m a stop bit and bus idle 0.55v cc / 0.45v cc 100 m s delay uvlo en connect PCA9508 sdaa scla sdab sclb v cc(a) v cc(b) connect v cc(b) pull-up resistor PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 4 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 5. pinning information 5.1 pinning 5.2 pin description 6. functional description refer to figure 1 functional diag r am of PCA9508 . the PCA9508 enables i 2 c-bus or smbus translation down to v cc(a) as low as 0.9 v without degradation of system performance. the PCA9508 contains two bidirectional open-drain buffers speci?cally designed to provide superior hot-swap and/or support up-translation/down-translation between the low voltage (as low as 0.9 v) and a 3.3 v or 5vi 2 c-bus or smbus. all inputs and i/os are overvoltage tolerant to 5.5 v even when the device is unpowered (v cc(b) and/or v cc(a) = 0 v). the PCA9508 includes a power-up circuit that keeps the output drivers turned off until v cc(b) is above 2.5 v and the v cc(a) is above 0.8 v. v cc(b) and v cc(a) can be applied in any sequence at power-up. v cc(a) is only used to provide the 0.5v cc(a) reference to the a side input comparators and for the power good detect circuit. the PCA9508 logic and all i/os are powered by the v cc(b) pin. an undervoltage/initialization circuit holds the PCA9508 in a disconnected state which presents high-impedance to all sda and scl pins during power-up. a low on the enable pin (en) also forces the parts into the disconnected state. as the power supply is brought up and en is high or the part is powered and en is taken from low to high it enters an initialization state where the internal references are stabilized. at the end of the initialization state the stop bit and bus idle detect circuit is enabled. with the en pin fig 2. pin con?guration for so8 fig 3. pin con?guration for tssop8 PCA9508d v cc(a) v cc(b) scla sclb sdaa sdab gnd en 002aac652 1 2 3 4 6 5 8 7 PCA9508dp v cc(a) v cc(b) scla sclb sdaa sdab gnd en 002aac653 1 2 3 4 6 5 8 7 table 3. pin description symbol pin description v cc(a) 1 a side supply voltage (0.9 v to 5.5 v) scla 2 open-drain input/output serial clock a side bus sdaa 3 open-drain input/output serial data a side bus gnd 4 supply ground (0 v) en 5 active high repeater enable input with an internal pull-up (100 k w) sdab 6 open-drain input/output serial data b side bus sclb 7 open-drain input/output serial clock b side bus v cc(b) 8 b side supply voltage (2.7 v to 5.5 v) PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 5 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater high long enough to complete the initialization state (t en ) and remaining high when all the sda and scl pins have been high for the bus idle time or when all pins are high and a stop condition is seen on the sdaa and scla pins, sdaa is connected to sdab and scla is connected to sclb. 6.1 a side to b side once connected, when the PCA9508 senses a low level on the a side (below 0.5v cc(a) ), it turns on the corresponding b side driver (either sda or scl) and drives the b side down to about 0.5 v. when the external driver turns off, the a side will begin to rise as it is pulled high by the bus pull-up resistor. when the a side reaches 0.5v cc(a) , the b side driver turns off and both a and b will continue to rise. the result is two smooth exponential rising edges on both buses with a propagation delay between them which is a function of the rc time constant on the a side bus. 6.2 b side to a side when a low level is sensed on the b side (below 0.4 v), the corresponding a side driver is turned on to drive the a side to nearly 0 v. when the external driver turns off, the b side will begin to rise as it is pulled high by the bus pull-up resistor. when the b side reaches 0.5 v, the a side driver will turn off. the b side driver will remain at about 0.5 v until the a side rises above 0.5v cc(a) , then the b side will continue to rise. the result is a plateau on the b side rising edge. see figure 11 . 6.3 weak drive on b side the following condition should be avoided as it causes the PCA9508 to create a glitch on the bus. as long as i 2 c-bus devices connected to the b side can pull the bus lines lower than 0.4 v, this problem will never occur. when the b side falls ?rst and goes below 0.3v cc(b) , the a side driver is turned on and the a side is pulled down to 0 v. the b side pull-down is switched on and unless the b side is pulled below 0.4 v by an external driver, the a side pull-down will switch off and the a side will be pulled up by the pull-up resistor. when the a side rises above 0.5v cc(a) , the b side pull-down will turn off. to prevent this glitch, it is necessary to make certain that the b side low level driven by an external driver is below 0.4 v. 6.4 enable pin (en) the en pin is active high with an internal pull-up to v cc(b) and allows the user to select when the repeater is active. this can be used to isolate a badly behaved slave on power-up until after the system power-up reset. it should never change state during an i 2 c-bus operation because disabling during a bus operation will hang the bus. the en pin should only change state when the global bus and the repeater port are in an idle state to prevent system failures. if the PCA9508 is enabled while the bus is active, the PCA9508 will connect at the ?rst stop signal or at the ?rst gap in activity that satis?es the internal idle bus time after the enable sequence is complete. PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 6 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 6.5 i 2 c-bus systems as with the standard i 2 c-bus system, pull-up resistors are required to provide the logic high levels on the buffered bus (standard open-collector con?guration of the i 2 c-bus). the size of these pull-up resistors depends on the system, but each side of the repeater must have a pull-up resistor. this part designed to work with standard-mode and fast-mode i 2 c-bus devices in addition to smbus devices. standard-mode i 2 c-bus devices only specify 3 ma output drive; this limits the termination current to 3 ma in a generic i 2 c-bus system where standard-mode devices and multiple masters are possible. under certain conditions higher termination currents can be used. please see application note an255, i 2 c/smbus repeaters, hubs and expanders for additional information on sizing resistors and precautions when using more than one PCA9508 in a system or using the PCA9508 in conjunction with other bus buffers. 7. application design-in information a typical application is shown in figure 4 . in this example, the system master is running on a 3.3 v i 2 c-bus while the slave is connected to a 1.2 v bus. both buses run at 400 khz. master devices can be placed on either bus. the PCA9508 is 5 v tolerant, so it does not require any additional circuitry to translate between 0.9 v to 5.5 v bus voltages and 2.7 v to 5.5 v bus voltages. when the a side of the PCA9508 is pulled low by a driver on the i 2 c-bus, a comparator detects the falling edge when it goes below 0.5v cc(a) and causes the internal driver on the b side to turn on, causing the b side to pull down to about 0.5 v. when the b side of the PCA9508 falls, ?rst a cmos hysteresis type input detects the falling edge and causes the internal driver on the a side to turn on and pull the a side pin down to ground. in order to illustrate what would be seen in a typical application, refer to figure 7 and figure 8 . if the bus master in figure 4 were to write to the slave through the PCA9508, waveforms shown in figure 7 would be observed on the a bus. this looks like a normal i 2 c-bus transmission except that the high level may be as low as 0.9 v, and the turn on and turn off of the acknowledge signals are slightly delayed. fig 4. typical application 002aac654 v cc(a) v cc(b) PCA9508 sdab sdaa sclb scla en 10 k w 10 k w sda scl bus master 400 khz slave 400 khz sda scl bus b bus a 1.2 v 3.3 v 10 k w 10 k w PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 7 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater on the b bus side of the PCA9508, the clock and data lines would have a positive offset from ground equal to the v ol of the PCA9508. after the 8 th clock pulse, the data line will be pulled to the v ol of the slave device, which is very close to ground in this example. at the end of the acknowledge, the level rises only to the low level set by the driver in the PCA9508 for a short delay while the a bus side rises above 0.5v cc(a) then it continues high. it is important to note that any arbitration or clock stretching events require that the low level on the b bus side at the input of the PCA9508 (v il ) be at or below 0.4 v to be recognized by the PCA9508 and then transmitted to the a bus side. multiple PCA9508 a sides can be connected in a star con?guration ( figure 5 ), allowing all nodes to communicate with each other. multiple PCA9508s can be connected in series ( figure 6 ) as long as the a side is connected to the b side. i 2 c-bus slave devices can be connected to any of the bus segments. the number of devices that can be connected in series is limited by repeater delay/time-of-?ight considerations on the maximum bus speed requirements. fig 5. typical star application v cc(b) v cc(a) PCA9508 sdaa sdab scla sclb en 10 k w 10 k w sda scl bus master slave 400 khz sda scl v cc(b) v cc(a) 10 k w 10 k w v cc(b) v cc(a) PCA9508 sdaa sdab scla sclb en 10 k w 10 k w slave 400 khz sda scl 002aac655 v cc(b) v cc(a) PCA9508 sdaa sdab scla sclb en 10 k w 10 k w slave 400 khz sda scl PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 8 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater fig 6. typical series application 002aac656 PCA9508 sdaa sdab scla sclb en sda scl bus master slave 400 khz sda scl 10 k w 10 k w PCA9508 sdaa sdab scla sclb en v cc PCA9508 sdaa sdab scla sclb en 10 k w 10 k w 10 k w 10 k w 10 k w 10 k w hot-swap and offset free hot-swap and offset free hot-swap and offset free fig 7. bus a (0.9 v to 5.5 v bus) waveform fig 8. bus b (2.7 v to 5.5 v) waveform 002aac204 9th clock pulse acknowledge scl sda 002aac657 9th clock pulse acknowledge scl sda v ol of slave v ol of PCA9508 PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 9 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 8. limiting values 9. static characteristics table 4. limiting values in accordance with the absolute maximum rating system (iec 60134). symbol parameter conditions min max unit v cc(b) supply voltage port b 2.7 v to 5.5 v - 0.5 +7 v v cc(a) supply voltage port a adjustable - 0.5 +7 v v i/o voltage on an input/output pin sdaa, sdab, scla, sclb, en - 0.5 +7 v i i input current any pin - 50 ma p tot total power dissipation - 100 mw t stg storage temperature - 55 +125 c t amb ambient temperature operating in free air - 40 +85 c t j junction temperature - +125 c table 5. static characteristics v cc =2.7v to 5.5v; gnd=0v; t amb = - 40 cto+85 c; unless otherwise speci?ed. symbol parameter conditions min typ max unit supplies v cc(b) supply voltage port b 2.7 - 5.5 v v cc(a) supply voltage port a [1] 0.9 - 5.5 v i cc(a) supply current port a pin v cc(a) --1 ma i cch high-level supply current both channels high; v cc = 5.5 v; sdan = scln = v cc - 1.5 3 ma i ccl low-level supply current both channels low; v cc = 5.5 v; one sda and one scl = gnd; other sda and scl open - 1.5 3 ma i cc(a)c contention port a supply current v cc = 5.5 v; sdan = scln = v cc - 1.5 3 ma input and output sdab and sclb v ih high-level input voltage 0.7v cc(b) - 5.5 v v il low-level input voltage [2] - 0.5 - +0.3v cc(b) v v ilc contention low-level input voltage - 0.5 0.4 - v v ik input clamping voltage i i = - 18 ma - - - 1.2 v i li input leakage current v i = 3.6 v - - 1 m a i il low-level input current sda, scl; v i = 0.2 v - - 10 m a v ol low-level output voltage i ol = 100 m a or 6 ma 0.47 0.52 0.6 v v ol - v ilc difference between low-level output and low-level input voltage contention guaranteed by design - - 70 mv i loh high-level output leakage current v o =v cc --10 m a c io input/output capacitance v i = 3 v or 0 v; v cc = 3.3 v - 5.2 7 pf v i = 3 v or 0 v; v cc = 0 v - 5.2 7 pf PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 10 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater [1] low-level supply voltage. [2] v il speci?cation is for the ?rst low level seen by the sdab/sclb lines. v ilc is for the second and subsequent low levels seen by the sdab/sclb lines. input and output sdaa and scla v ih high-level input voltage 0.6v cc(a) 0.5v cc(a) 5.5 v v il low-level input voltage - 0.5 - +0.4v cc(a) v v ik input clamping voltage i i = - 18 ma - - - 1.2 v i li input leakage current v i = 3.6 v - - 1 m a i il low-level input current sda, scl; v i = 0.2 v - - 10 m a v ol low-level output voltage i ol = 6 ma - 0.1 0.2 v i loh high-level output leakage current v o =v cc --10 m a c io input/output capacitance v i = 3 v or 0 v; v cc = 3.3 v - 5.2 7 pf v i = 3 v or 0 v; v cc = 0 v - 5.2 7 pf enable v il low-level input voltage - 0.5 - +0.3v cc(b) v v ih high-level input voltage 0.7v cc(b) - 5.5 v i il(en) low-level input current on pin en v i = 0.2 v, en; v cc = 3.6 v - - 10 - 30 m a i li input leakage current v i =v cc - 1- +1 m a c i input capacitance v i = 3.0 v or 0 v - 1.7 7 pf table 5. static characteristics continued v cc =2.7v to 5.5v; gnd=0v; t amb = - 40 cto+85 c; unless otherwise speci?ed. symbol parameter conditions min typ max unit PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 11 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 10. dynamic characteristics [1] times are speci?ed with loads of 1.35 k w pull-up resistance and 57 pf load capacitance on the b side, and 167 w pull-up resistance and 57 pf load capacitance on the a side. different load resistance and capacitance will alter the rc time constant, thereby chan ging the propagation delay and transition times. [2] pull-up voltages are v cc(a) on the a side and v cc(b) on the b side. [3] typical values were measured with v cc(a) = 3.3 v at t amb =25 c, unless otherwise noted. [4] the t plh delay data from b side to a side is measured at 0.5 v on the b side to 0.5v cc(a) on the a side when v cc(a) is less than 2 v, and 1.5 v on the a side if v cc(a) is greater than 2 v. [5] typical value measured with v cc(a) = 2.7 v at t amb =25 c. [6] the proportional delay data from a side to b side is measured at 0.3v cc(a) on the a side to 1.5 v on the b side. [7] de?ned as the time required to connect from b side to a side, after b side switches from active to idle, when a side is idle. [8] de?ned as the time required to connect from b side to a side, when b side and a side are idle. [9] de?ned as the time required to connect a side to b side, when b side is idle and a side is going active from idle, by a stop con dition. [10] the enable pin, en, should only change state when the global bus and the repeater port are in an idle state. table 6. dynamic characteristics v cc =2.7v to 5.5v; gnd=0v; t amb = - 40 cto+85 c; unless otherwise speci?ed. [1] [2] symbol parameter conditions min typ [3] max unit t plh low-to-high propagation delay b side to a side; figure 11 [4] 100 170 250 ns t phl high-to-low propagation delay b side to a side; figure 9 v cc(a) < 3.0 v [5] 20 98 118 ns v cc(a) > 3.0 v 20 76 164 ns t tlh low to high output transition time a side; figure 10 10 20 30 ns t thl high to low output transition time a side; figure 10 v cc(a) < 2.7 v [5] 1 7283ns v cc(a) > 3.0 v 8 68 137 ns t plh low-to-high propagation delay a side to b side; figure 10 [6] 25 53 110 ns t phl high-to-low propagation delay a side to b side; figure 10 [6] 60 79 230 ns t tlh low to high output transition time b side; figure 9 120 140 170 ns t thl high to low output transition time b side; figure 9 30 48 90 ns t connect connect time [7] b side to a side; figure 12 - 0.5 - m s t idle(connect) connect idle time [8] b side to a side; figure 13 50 105 200 m s t stop(connect) connect stop time [9] a side to b side; figure 14 - 0.5 - m s t su set-up time en high before start condition [10] 100 - - ns t h hold time en high after stop condition [10] 100 - - ns PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 12 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 10.1 ac waveforms fig 9. propagation delay and transition times; b side to a side fig 10. propagation delay and transition times; a side to b side fig 11. propagation delay; b side to a side 002aad642 3.0 v 1.2 v t plh t thl 1.5 v 1.5 v input output 20 % 0.6 v 0.6 v 80 % 20 % 80 % t phl t tlh v ol 0.1 v 002aad643 v cc(a) 3.0 v t plh t thl 0.3v cc(a) 0.3v cc(a) input output 20 % 1.5 v 1.5 v 80 % 20 % 80 % t phl t tlh 0.5 v input sdab, sclb output scla, sdaa t plh 50 % if v cc(a) is less than 2 v 1.5 v if v cc(a) is greater than 2 v 002aad641 PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 13 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater fig 12. t connect timing fig 13. t idle(connect) timing fig 14. t stop(connect) timing en sdaa sclb sdab scla wait 200 m s move until scla goes low 002aad716 v cc 0 v en scla sdab sclb sdaa wait 200 m s move until sdaa goes low v cc 0 v v cc 0 v v cc 0 v t connect t connect en sclb sdab sdaa scla move until sdaa goes low 002aad717 en sdab sclb scla sdaa v cc 0 v v cc 0 v v cc 0 v move until scla goes low v cc 0 v v cc 0 v t idle(connect) t idle(connect) 002aad718 en scla sdaa sclb sdab move until sclb goes low v cc 0 v v cc 0 v t stop(connect) PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 14 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 11. test information r l = load resistor; 1.35 k w on b side; 167 w on a side c l = load capacitance includes jig and probe capacitance; 57 pf r t = termination resistance should be equal to z o of pulse generators fig 15. test circuit for open-drain outputs pulse generator v o c l r l 002aab649 r t v i v cc(b) v cc(b) dut v cc(a) PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 15 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 12. package outline fig 16. package outline sot96-1 (so8) unit a max. a 1 a 2 a 3 b p cd (1) e (2) (1) eh e ll p qz y w v q references outline version european projection issue date iec jedec jeita mm inches 1.75 0.25 0.10 1.45 1.25 0.25 0.49 0.36 0.25 0.19 5.0 4.8 4.0 3.8 1.27 6.2 5.8 1.05 0.7 0.6 0.7 0.3 8 0 o o 0.25 0.1 0.25 dimensions (inch dimensions are derived from the original mm dimensions) notes 1. plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. 2. plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included. 1.0 0.4 sot96-1 x w m q a a 1 a 2 b p d h e l p q detail x e z e c l v m a (a ) 3 a 4 5 pin 1 index 1 8 y 076e03 ms-012 0.069 0.010 0.004 0.057 0.049 0.01 0.019 0.014 0.0100 0.0075 0.20 0.19 0.16 0.15 0.05 0.244 0.228 0.028 0.024 0.028 0.012 0.01 0.01 0.041 0.004 0.039 0.016 0 2.5 5 mm scale so8: plastic small outline package; 8 leads; body width 3.9 mm sot96-1 99-12-27 03-02-18 PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 16 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater fig 17. package outline sot505-1 (tssop8) unit a 1 a max. a 2 a 3 b p l h e l p wy v ce d (1) e (2) z (1) q references outline version european projection issue date iec jedec jeita mm 0.15 0.05 0.95 0.80 0.45 0.25 0.28 0.15 3.1 2.9 3.1 2.9 0.65 5.1 4.7 0.70 0.35 6 0 0.1 0.1 0.1 0.94 dimensions (mm are the original dimensions) notes 1. plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. plastic or metal protrusions of 0.25 mm maximum per side are not included. 0.7 0.4 sot505-1 99-04-09 03-02-18 w m b p d z e 0.25 14 8 5 q a a 2 a 1 l p (a 3 ) detail x l h e e c v m a x a y 2.5 5 mm 0 scale tssop8: plastic thin shrink small outline package; 8 leads; body width 3 mm sot505-1 1.1 pin 1 index PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 17 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 13. soldering of smd packages this text provides a very brief insight into a complex technology. a more in-depth account of soldering ics can be found in application note an10365 surface mount re?ow soldering description . 13.1 introduction to soldering soldering is one of the most common methods through which packages are attached to printed circuit boards (pcbs), to form electrical circuits. the soldered joint provides both the mechanical and the electrical connection. there is no single soldering method that is ideal for all ic packages. wave soldering is often preferred when through-hole and surface mount devices (smds) are mixed on one printed wiring board; however, it is not suitable for ?ne pitch smds. re?ow soldering is ideal for the small pitches and high densities that come with increased miniaturization. 13.2 wave and re?ow soldering wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. the wave soldering process is suitable for the following: ? through-hole components ? leaded or leadless smds, which are glued to the surface of the printed circuit board not all smds can be wave soldered. packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. also, leaded smds with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. the re?ow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature pro?le. leaded packages, packages with solder balls, and leadless packages are all re?ow solderable. key characteristics in both wave and re?ow soldering are: ? board speci?cations, including the board ?nish, solder masks and vias ? package footprints, including solder thieves and orientation ? the moisture sensitivity level of the packages ? package placement ? inspection and repair ? lead-free soldering versus snpb soldering 13.3 wave soldering key characteristics in wave soldering are: ? process issues, such as application of adhesive and ?ux, clinching of leads, board transport, the solder wave parameters, and the time during which components are exposed to the wave ? solder bath speci?cations, including temperature and impurities PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 18 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 13.4 re?ow soldering key characteristics in re?ow soldering are: ? lead-free versus snpb soldering; note that a lead-free re?ow process usually leads to higher minimum peak temperatures (see figure 18 ) than a snpb process, thus reducing the process window ? solder paste printing issues including smearing, release, and adjusting the process window for a mix of large and small components on one board ? re?ow temperature pro?le; this pro?le includes preheat, re?ow (in which the board is heated to the peak temperature) and cooling down. it is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). in addition, the peak temperature must be low enough that the packages and/or boards are not damaged. the peak temperature of the package depends on package thickness and volume and is classi?ed in accordance with t ab le 7 and 8 moisture sensitivity precautions, as indicated on the packing, must be respected at all times. studies have shown that small packages reach higher temperatures during re?ow soldering, see figure 18 . table 7. snpb eutectic process (from j-std-020c) package thickness (mm) package re?ow temperature ( c) volume (mm 3 ) < 350 3 350 < 2.5 235 220 3 2.5 220 220 table 8. lead-free process (from j-std-020c) package thickness (mm) package re?ow temperature ( c) volume (mm 3 ) < 350 350 to 2000 > 2000 < 1.6 260 260 260 1.6 to 2.5 260 250 245 > 2.5 250 245 245 PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 19 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater for further information on temperature pro?les, refer to application note an10365 surface mount re?ow soldering description . 14. abbreviations 15. revision history msl: moisture sensitivity level fig 18. temperature pro?les for large and small components 001aac844 temperature time minimum peak temperature = minimum soldering temperature maximum peak temperature = msl limit, damage level peak temperature table 9. abbreviations acronym description cdm charged-device model cmos complementary metal-oxide semiconductor dut device under test esd electrostatic discharge hbm human body model i 2 c-bus inter-integrated circuit bus i/o input/output mm machine model rc resistor-capacitor network smbus system management bus table 10. revision history document id release date data sheet status change notice supersedes PCA9508_1 20080428 product data sheet - - PCA9508_1 ? nxp b.v. 2008. all rights reserved. product data sheet rev. 01 28 april 2008 20 of 21 nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater 16. legal information 16.1 data sheet status [1] please consult the most recently issued document before initiating or completing a design. [2] the term short data sheet is explained in section de?nitions. [3] the product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple dev ices. the latest product status information is available on the internet at url http://www .nxp .com . 16.2 de?nitions draft the document is a draft version only. the content is still under internal review and subject to formal approval, which may result in modi?cations or additions. nxp semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. short data sheet a short data sheet is an extract from a full data sheet with the same product type number(s) and title. a short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. for detailed and full information see the relevant full data sheet, which is available on request via the local nxp semiconductors sales of?ce. in case of any inconsistency or con?ict with the short data sheet, the full data sheet shall prevail. 16.3 disclaimers general information in this document is believed to be accurate and reliable. however, nxp semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. right to make changes nxp semiconductors reserves the right to make changes to information published in this document, including without limitation speci?cations and product descriptions, at any time and without notice. this document supersedes and replaces all information supplied prior to the publication hereof. suitability for use nxp semiconductors products are not designed, authorized or warranted to be suitable for use in medical, military, aircraft, space or life support equipment, nor in applications where failure or malfunction of an nxp semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental damage. nxp semiconductors accepts no liability for inclusion and/or use of nxp semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customers own risk. applications applications that are described herein for any of these products are for illustrative purposes only. nxp semiconductors makes no representation or warranty that such applications will be suitable for the speci?ed use without further testing or modi?cation. limiting values stress above one or more limiting values (as de?ned in the absolute maximum ratings system of iec 60134) may cause permanent damage to the device. limiting values are stress ratings only and operation of the device at these or any other conditions above those given in the characteristics sections of this document is not implied. exposure to limiting values for extended periods may affect device reliability. terms and conditions of sale nxp semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www .nxp .com/pro? le/ter ms , including those pertaining to warranty, intellectual property rights infringement and limitation of liability, unless explicitly otherwise agreed to in writing by nxp semiconductors. in case of any inconsistency or con?ict between information in this document and such terms and conditions, the latter will prevail. no offer to sell or license nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. 16.4 trademarks notice: all referenced brands, product names, service names and trademarks are the property of their respective owners. i 2 c-bus logo is a trademark of nxp b.v. 17. contact information for more information, please visit: http://www .nxp.com for sales of?ce addresses, please send an email to: salesad dresses@nxp.com document status [1] [2] product status [3] de?nition objective [short] data sheet development this document contains data from the objective speci?cation for product development. preliminary [short] data sheet quali?cation this document contains data from the preliminary speci?cation. product [short] data sheet production this document contains the product speci?cation. nxp semiconductors PCA9508 hot swappable level translating i 2 c-bus repeater ? nxp b.v. 2008. all rights reserved. for more information, please visit: http://www.nxp.com for sales office addresses, please send an email to: salesaddresses@nxp.com date of release: 28 april 2008 document identifier: PCA9508_1 please be aware that important notices concerning this document and the product(s) described herein, have been included in section legal information. 18. contents 1 general description . . . . . . . . . . . . . . . . . . . . . . 1 2 features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3 ordering information . . . . . . . . . . . . . . . . . . . . . 3 4 functional diagram . . . . . . . . . . . . . . . . . . . . . . 3 5 pinning information . . . . . . . . . . . . . . . . . . . . . . 4 5.1 pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 5.2 pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4 6 functional description . . . . . . . . . . . . . . . . . . . 4 6.1 a side to b side. . . . . . . . . . . . . . . . . . . . . . . . . 5 6.2 b side to a side. . . . . . . . . . . . . . . . . . . . . . . . . 5 6.3 weak drive on b side . . . . . . . . . . . . . . . . . . . . 5 6.4 enable pin (en) . . . . . . . . . . . . . . . . . . . . . . . . 5 6.5 i 2 c-bus systems . . . . . . . . . . . . . . . . . . . . . . . . 6 7 application design-in information . . . . . . . . . . 6 8 limiting values. . . . . . . . . . . . . . . . . . . . . . . . . . 9 9 static characteristics. . . . . . . . . . . . . . . . . . . . . 9 10 dynamic characteristics . . . . . . . . . . . . . . . . . 11 10.1 ac waveforms. . . . . . . . . . . . . . . . . . . . . . . . . 12 11 test information . . . . . . . . . . . . . . . . . . . . . . . . 14 12 package outline . . . . . . . . . . . . . . . . . . . . . . . . 15 13 soldering of smd packages . . . . . . . . . . . . . . 17 13.1 introduction to soldering . . . . . . . . . . . . . . . . . 17 13.2 wave and re?ow soldering . . . . . . . . . . . . . . . 17 13.3 wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 17 13.4 re?ow soldering . . . . . . . . . . . . . . . . . . . . . . . 18 14 abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 19 15 revision history . . . . . . . . . . . . . . . . . . . . . . . . 19 16 legal information. . . . . . . . . . . . . . . . . . . . . . . 20 16.1 data sheet status . . . . . . . . . . . . . . . . . . . . . . 20 16.2 de?nitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 16.3 disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 16.4 trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 17 contact information. . . . . . . . . . . . . . . . . . . . . 20 18 contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 |
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