H11L1 optocoupler — ignition coil(−) response

R116 = 1.2 kΩ · coil flyback peak = 300 V

Three cycles of a Kettering coil waveform (dwell → 300 V flyback → 50 V burn → ringing → 13 V open). Move the pointer over any panel to read all three signals at one time instant.

0100200300Coil(−) input voltage (V)300 V 0100200300H11L1 LED current (mA)247 mA9.8 mAH11L1 I_F(pk) limit = 100 mA 0 ms5 ms10 ms15 ms20 ms25 ms30 msH11L1 LED light on/offonoff