A high power light triggered triac with a novel light sensitive structure

A high power light triggered triac with novel gate structure is presented, which consists of two thyristors connected in inverse parallel and one light emitting diode provided over a cone-shaped groove light sensitive gate between the thyristors. The light trigger characteristics have been studied, and some manufacturing techniques are also described. A 500-A, 1200-V, 40-mm diameter light triggered triac has been developed. This device has the characteristics of the minimum light triggering power of less than 15 mw, the on-state voltage of less than 1.6 V, the commutating dV/dt capability of 100 V/μs, and the commutating di/dt capability of 50 A/μs