An optically toggled bidirectional normally-on switch is provided with protection against bilateral voltage and bidirectional current surges by the inclusion of a pair of oppositely poled thyristors. One version uses a large junction-type field-effect transistor in its main path and a pair of smaller junction-type transistors in the subsidiary path. A photodiode array controls the gate voltage on each of the transistors and turns them off when illuminated. A control node in the subsidiary path is connected to the gates of the SCRs so that excess current in this path turns on the appropriately-poled thyristor to provide an additional shunt path for the current.
申请公布号
US4424544(A)
申请公布日期
1984.01.03
申请号
US19820347299
申请日期
1982.02.09
申请人
BELL TELEPHONE LABORATORIES, INCORPORATED
发明人
CHANG, GEE-KUNG;EL HAMAMSY, MAHMOUD A.;HARTMAN, ADRIAN R.;LORIMOR, ORVAL G.