Patent ID: 7791793

Claim:
A drive circuit for a semiconductor optical amplifier gate switch that is connectable to an anode of each of a plurality of semiconductor optical amplifier gate switches, the drive circuit comprising: a plurality of operational amplifiers that are connected in parallel with each other; a first transmission path that transmits a signal generated by a signal source to each of the operational amplifiers, wherein the first transmission path includes a common first sub-path that commonly transmits a signal from the signal source to a first node; and an individual second sub-path for each of the operational amplifiers that separately transmits the signal from the first node to a corresponding one of the operational amplifiers; and a second transmission path that transmits a signal output from the operational amplifiers to the semiconductor optical amplifier gate switches, wherein the second transmission path includes an individual third sub-path for each of the operational amplifiers that separately transmits a signal from a corresponding one of the operational amplifiers to a second node; and a common fourth sub-path that commonly transmits the signal from the second node to the semiconductor optical amplifier gate switches, wherein transmission delay times of all the individual second sub-paths are equal, and transmission delay times of all the individual third sub-paths are equal.