Demonstrating the effect of dv/dt turn-on in a Thyristor.
For a Thyristor or SCR in the non-conducting state - even with the gate tied to the cathode - as the rate of change of voltage (dv/dt) across the anode and cathode terminals exceeds the datasheet specified maximum value (in this case 30V/us), the device will turn on.
A similar effect occurs in Diacs and Triacs.
This simulation uses the EasyEDA Thyristor model. For more on this model see:
To run the simulation:
|1||Pulse(1 2.1 2.5u)||V2||1|
|2||V=LIMIT(0, 15, V(gen))||B1||1|
|6||Pulse(0 15 0 1u 10n 1u 3u)||V1||1|