A HIGH-POWER LIGHT-TRIGGERED TRIAC WITH A NOVEL LIGHT-SENSITIVE STRUCTURE

A high power light triggered triac with novel gate structure is presen ted, which consists of two thyristors connected in inverse parallel an d one light emitting diode provided over a cone-shaped groove light se nsitive gate between the thyristors. The light trigger characteristics have been studied, and some manufacturing techniques are also describ ed. A 500-A, 1200-V, 40-mm diameter light triggered triac has been dev eloped. This device has the characteristics of the minimum light trigg ering power of less than 15 mw, the on-state voltage of less than 1.6 V, the commutating dV/dt capability of 100 V/mu s, and the commutating di/dt capability of 50 A/mu s.