onsemi (Ansemi)

SOIC-8

taping

2500

The FAN1100_F085 is used to directly drive the ignition IGBT, controlling the coil current and spark event. The coil current is controlled through the input pin. When the input is driven high, the output of the FAN1100_F085 is enabled to turn on the IGBT and start coil charging. The FAN1100_F085 sinks current (IIN) into the input pin based on the programmed current on the RA line. The input spike filter rejects input signals with a duration of less than 13 µsec. A maximum dwell timer is included in FAN1100_F085 to turn off the IGBT if the input remains active for longer than the programmed time. This time interval can be modified by an external capacitor on CSSD. When the maximum dwell timer is exceeded, the FAN1100_F085 will enter Soft Shutdown Mode (SSD) to slowly reduce the collector current by slowing down the gate driver speed of the IGBT, thereby discharging the coil and inhibiting events such as sparking. Once the soft-shutdown operation is initiated, any transitions on the input signal are ignored until the soft-shutdown function is complete. FAN1100_F085 will also limit the collector current of the IGBT to Ic(lim) during charging. This is also done through a sense resistor in the firing IGBT emitter leg that generates the signal input into the Vsense pin of the FAN1100_F085.