Posted on Jul 18, 2012 5231
The HllC supplies the de latching relay function and reverse polarity blocking, for currents up to 300 mA, depending on ambient temperature. For de use, the gate cathode resistor can be supplemented by a capacitor to minimize transient and dV/dt sensitivity. For pulsating de operation, the capacitor value must be designated to either retrigger the SCR at the application of the next pulse or prevent retriggering at the next power pulse.
If not, random or undesired operation might occur. For higher current contacts, the HllC can be used to trigger an SCR capable of handling the current, as illustrated.