bidirectional switch motor stop controlled by motor current start up and end current detec- tion thresholds programmable with external rshunt stop delay time for start up and end phase programmable with ex- ternal rc output short circuit protection output current limiting > 8a thermal protection active diode bridge internally dif- fused maximum voltage supply 50v technology multipower bcd60ii november 1998 ? common 19 active bridge gnd 1,10,11,20 live 2 v+ 14 pow er on reset logic hv ref. voltage thermal protec t. charge cex. control logic lv open load detector charge pump current protect. power dual dmos comp. vref s h u n t 534 6 17 16 rcex 8 ref. comp. current block diagram powerso20 L9639 folder actuator 1/6 obsolete product(s) - obsolete product(s)
absolute maximum ratings symbol parameter value unit v bat supply voltage 50 v i out output current dc at is 5 6 a a t op operating temperature -40 to 125 c thermal data symbol parameter value unit r th j-case thermal resistance junction to case max. 4 c/w live common nc gnd out out nc v+ gnd nc gnd shunt shunt shunt gnd rcex nc nc nc vref 2 7 1 3 4 5 10 8 9 6 19 14 20 18 17 16 11 13 12 15 pin connection L9639 2/6 obsolete product(s) - obsolete product(s)
description this device typically drives a direct current motor servomechanism providing two extreme end posi- tions and replaces end position switches or sen- sors. for more details see the timing diagram (fig. 1) and the application diagram (fig. 2) when the power supply is applied, or its polarity is inverted the motor is powered up (start point). the current of the motor reaches the start up value near to the stall current, always higher than the threshold value of the device (i th ) . a delay on the detection (t d ) permits the motor start up and the consequent decrease of the current. during the free running phase, the current in the motor must always be lower the threshold i th . when the motor reaches the end of the run limit, the current increases reaching a value that, de- pending on the application, can be the stall value or can depend on some torque limiting friction (end point). provided that this value is higher the programmed threshold i th , the motor is stopped after a time delay t d , and the device goes into a low consumption standby status, ready to restart the motor for a new cycle if the polarity of the power supply is inverted (or power is switched off and on). in any case, if the current exceeds the higher threshold i thcc , the motor is immediately stopped because a short circuit is detected. the delay t d also permits the motor to overcome some small obstacle during the free run. the threshold current for the running phase i th is obtained by comparing the voltage on an external sensing resistor (r shunt ) to a threshold voltage v th . 1) i th =v th /r shunt v th is constant in respect to the power supply voltage because in most applications, the end of run current is depending only on motor and the mechanic torque limiting device (friction current). the threshold current for the short circuit detec- tion is: 2) i thcc =v thcc /r shunt @v thcc = 330mv @ v bat = 12v and depends intentionally on the supply voltage because of the same dependence of the stall cur- rent. the time t d depends on two external com- ponents, capacitor c ex and resistor r ex .tdis obtained by the following expression : t d =r ex ? r ex ? k td k td is a constant typically of unit value. the block diagram is shown on the first page. the change of the polarity between pins com- mon and live, needs the active bridge to supply the internal circuit. the internal supply voltage is available between pins v+ and gnd and a stor- age and filter capacitor (100nf) must be con- nected between these pins. the output stage electrical characteristics (refer to the test circuit, unless otherwise specified.) symbol parameter test condition min. typ. max. unit v bat power supply 8 17 v i q quiescent current stanby 100 200 m a i ref current ref. threshold for start and end current (note 1) v bat = 8 to 17v 70 100 135 m a i refcc current ref. threshold for short circuit current det (note 2) vbat = 8v v bat = 12v v bat = 17v 240 300 400 300 440 550 400 560 690 m a i sc1 current short circuit limit 8 a t dsc short circuit time delay i load >i thcc 100 m s r on r on output power dmos i load = 1.2a 0.6 1 ohm r ona r on active bridge dmos v bat = 8v, i gnd = 1a 0.7 ohm r load open load detector max. load resistance 200 ohm k td delay constant (note 3) 1 deb immunity debouncer switch v bat = pulse note 1: i th = r_ref r shunt i ref note 2: i thcc = r_ref r shunt ? i refcc note 3: t d = in ? ? ? v th_high v th_low ? ? ? ? rex ? cex = rex ? cex ? ktd L9639 3/6 obsolete product(s) - obsolete product(s)
consists of two dmos transistors connected in series with common drain to act as a switch with the voltage applied in both direction. a charge pump takes the gates of the dmos above the supply voltage. the motor is controlled by the control 'logic low voltage' block that receives the motor status for the comparator. the 'charge c ex ' block controls the t d delay. 1 2 3 ith ithcc stall current 2.3a friction 1.2a vth_high vth_low figure 1. functional timing diagram. live common nc gnd out out nc v+ gnd nc gnd shunt shunt shunt gnd rcex r_shunt r_ref m c+ c_ex r_ex nc nc nc vref figure 2. application schematic diagram. all the necessary external components are shown in the application diagram. it is important to shunt the motor with a device that limits the maximum over voltage to 40v. this is necessary when the power sup- ply circuit is opened on motor power up. in this case the back e.m.f. must be clamped because there is no other free wheel current path. L9639 4/6 obsolete product(s) - obsolete product(s)
jedec mo-166 powerso20 e a2 a e a1 pso20mec detail a t d 1 11 20 e1 e2 hx 45 detail a lead slug a3 s gage plane 0.35 l detail b r detail b (coplanarity) gc -c- seating plane e3 b c n n h bottom view e3 d1 dim. mm inch min. typ. max. min. typ. max. a 3.6 0.142 a1 0.1 0.3 0.004 0.012 a2 3.3 0.130 a3 0 0.1 0.000 0.004 b 0.4 0.53 0.016 0.021 c 0.23 0.32 0.009 0.013 d (1) 15.8 16 0.622 0.630 d1 9.4 9.8 0.370 0.386 e 13.9 14.5 0.547 0.570 e 1.27 0.050 e3 11.43 0.450 e1 (1) 10.9 11.1 0.429 0.437 e2 2.9 0.114 e3 5.8 6.2 0.228 0.244 g 0 0.1 0.000 0.004 h 15.5 15.9 0.610 0.626 h 1.1 0.043 l 0.8 1.1 0.031 0.043 n10 (max.) s t 10 0.394 (1) od and fo do not include mold flash or protrusions. - mold flash or protrusions shall not exceed 0.15 mm (0.006o). - critical dimensions: oeo, ogo and oa3o outline and mechanical data 8 (max.) 10 L9639 5/6 obsolete product(s) - obsolete product(s)
information furnished is believed to be accurate and reliable. however, stmicroelectronics assumes no responsibility for the consequences of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. no license is granted by implication or otherwise under any patent or patent rights of stmicroelectronics. specification mentioned in this publication are subject to change without notice. this publication supersedes and replaces all information previously supplied. stmicroelectronics products are not authorized for use as critical components in life support devices or systems without express written approval of stmicroelectronics. the st logo is a registered trademark of stmicroelectronics ? 1998 stmicroelectronics printed in italy all rights reserved stmicroelectronics group of companies australia - brazil - canada - china - france - germany - italy - japan - korea - malaysia - malta - mexico - morocco - the netherlands - singapore - spain - sweden - switzerland - taiwan - thailand - united kingdom - u.s.a. http://www.st.com L9639 6/6 obsolete product(s) - obsolete product(s)
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