unisonic technologies co., ltd ul497 preliminary linear integrated circuit www.unisonic.com.tw 1 of 8 copyright ? 2013 unisonic technologies co., ltd qw-r118-015.a hall effect pickup ignition controller ? description as an integrated electronic igniti on controller for breakerless ignition systems which uses hall effect sensors, the utc ul497 drives an npn external darlington to control the coil current providing the required stored energy with low dissipation. one of the utc ul497 special features is the programmable time for the recovery of the correct dwell ratio td/t while the coil peak current fails to reach 94 % of the nominal value. ? features * direct driving of the external power darlington * coil current charent charging angle control * programme coil current peak limitation * when 94% nominal current not reached programmable dwell recovery time * rpm output * has peranent conduction protection * overvoltage protection * internal supply zener * reverse battery protection ? ordering information ordering number package packing lead free halogen free UL497L-S16-R ul497g-s16-r sop-16 tape reel ul497l-s16-t ul497g-s16-t sop-16 tube
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 2 of 8 www.unisonic.com.tw qw-r118-015.a ? pin configuration ? pin description (refer to application circuit) pin no. pin name description 1 gnd this pin must be connected to ground. 2 signal gnd this pin must be connected to ground. 3 power supply the input of supply voltage. its voltage will be limited by an 7.5v zener. the r5 inside will limit the current by the zener for high supply voltege. 4 n.c. connected to ground or left open. 5 hall-effect input the input of the hall-effect pickup signal . this input is dwell control circuit output to enable the current driving into the coil. 6 rpm output as a open collector output, it?s at low level when current flows in the ignition coil. it should be connected pin7 zener for high volteges protection. then r 8 must limit the zener current, too, and r 1 limits pin 6 current if rpm module pad is accidentally connected to v s. 7 aux. zener a 21v zener whose current mu st be limited by an internal resistor. 8 recovery time a capacitor connected between this pin and ground sets the slope of the dwell time variation as it rises from zero to the correct val ue. it occurs just following the detection of i coll 94% i nom , only before the low transition of the hall-effect signal pulse. the duration is given : t src =12.9r 7src c src (ms) ps: r 7 (k ? ) is the biasing resistor at pin 12 and c src ( f) is the delay capacitor at pin 8. 9 max conduction time between this pin and ground there?s a capacitor which determines the intervention delay of the permanent cond uction protection. the coil current is slowly reduced to zero after the delay time. delay time t p is given by : t p =16r 7 c p (ms) ps: r 7 (k ? ) is the biasing resistor at pin 12 and c p ( f) is the delay capacitor at pin 9. 10 dwell control timer connected between this pin and ground there?s a capacitor c t which is charged when the hall effect output is high and is discharged at the high to low transition of the hall effect signal. when using a 62k ? resistor at pin12 c t should be 100nf.
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 3 of 8 www.unisonic.com.tw qw-r118-015.a ? pin description (cont.) pin no. pin name description 11 dwell control the average voltage on the capacitor cw connected between this pin and ground depends on the motor speed and the voltage supply. the comparison between v cw and v ct voltage determines the timi ng for the dwell control. 12 bias current the internal current which used to driv e the external capacitors of the dwell control(pin10 and11)permanent conduc tion protection (pin 9) and slow recovery time (pin 8) can be set by a resistor(recommended 62k ? ) connected between this pin and ground. 13 current sensing connection for the coil current limitation. the current limitation value is given by : i sens =0.32(r10+r11)(r s r11) rs: sensing resistor 14 driver emitter output current driver for the external darlington. 15 over voltage limit the internal divider r 3 /r 2 defines the limitation value given by: v ovp =(22.5/r3+510 -3 )r 2 +22.5 16 driver collector input through this pin the collector current of the internal driver which drives the external limits darlington is suppli ed. then the external resistor r 6 the maximum current supplied to the base of the external darlington.
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 4 of 8 www.unisonic.com.tw qw-r118-015.a ? block diagram rpm max time gnd single gnd n.c. current sensing driver emitter output over voltage limit driver collection input rpm output power supply bias current hall effect input dwell control dwell control recover time aux zener slow recovery circuit reference dwell control control switch driving stage current limiter over voltage protection desaturation sensor permanent conduction protection 3 6 16 12 5 10 11 8 7 9 1 2 4 13 14 15
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 5 of 8 www.unisonic.com.tw qw-r118-015.a ? absolute maximum rating parameter symbol ratings unit d.c. supply current i 3 200 ma transient supply current t f fall time constant=100ms 800 ma supply voltage v 3 internal limited to vz 3 rpm voltage v 6 28 v d.c. driver collector current i 16 300 ma pulse (t 3ms) 600 ma driver collector voltage v 16 28 v auxiliary zener current i 7 40 ma d.c. overvoltage zener current pulse t fall =300 s i 15 15 ma t re p repetition time 3ms 35 ma reverse battery voltage if application circuit v r -16 v power dissipation t c =90c p d 1.2 w junction temperature t j -55~150 c storage temperature t stg -55~150 c note: absolute maximum ratings are those values beyond which the device could be permanently damaged. absolute maximum ratings are stress ratings only and functional device oper ation is not implied. ? thermal data parameter symbol ratings unit junction to ambient (note) ja 50 (max) c/w note: thermal resistance junction ambient with the device soldered on the middle of an ambient supporting substrate measuring 15x20; 0.65mm thickness.
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 6 of 8 www.unisonic.com.tw qw-r118-015.a ? electrical characteristics (v s =14.4v, -40 c ul497 preliminary linear integrated circuit unisonic technologies co., ltd 7 of 8 www.unisonic.com.tw qw-r118-015.a ? application information fig 1. main waveform
ul497 preliminary linear integrated circuit unisonic technologies co., ltd 8 of 8 www.unisonic.com.tw qw-r118-015.a ? typical application circuit 12 10 11 18 9 2 c p 1f c src 1f c w 0.1f c t 0.1f r7 62k i bias 7 4 5 6 hall effect sensor c s 0.22f d zi 24v r8 820 r1 100 20 r4 r5 100 24v d zz r6 56 4.3k t1 v s + c o r o 5k r2 r3 350 q1 r10 200 rc 10k c c r9 2k r s 75m r11 100 v sens gnd bu931r 16 15 14 13 utc ul497 3 rpm 2.2nf h+ fig 2. application circuit utc assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all utc products described or contained herein. utc products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. the information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice.
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