A method of controlling an optical PNPN thyristor.

摘要

The method comprises the step of applying a train of pulses (313) across the anode (33) and cathode (36) of the thyristor to maintain a low impedance state of an optical pnpn thyristor which is shifted beforehand to be in a low impedance state by a positive set pulse (311). Each of the train of pulses (313) is less than in its level than the positive set pulse (311). When light emission is required for the reading of information, another positive set pulse (312) is applied to the optical pnpn thyristor. As a result, electric power consumption is reduced during a time storing the information. The train of pulses (313) may be superimposed on a low bias voltage (Vb1).