| 摘要 |
PROBLEM TO BE SOLVED: To reduce the power consumption by connecting the electric control input terminal of a j-th optical gate element to the connector of a j-th transistor and also connecting each emitter of plural transistors to a single power supply. SOLUTION: If a high level electric control input current is inputted to any one of electric control input terminal ICs and low level electric currents are inputted to other input terminals, optical signals are passed only through the gate circuit LGj into which a high level electric control input current is inputted. In the emitter coupled transistors Q1 to Qn, if a high level signal is supplied to the base of a transistor Qj and low level signals are supplied to the bases of the rest of transistors, only the transistor, to which a high level signal is supplied, is made conductive and other transistors are put into their shutting off conditions. Thus, by switching electric control input currents, optical signals are switched and electric control input currents are collectively adjusted. |
