| 摘要 |
PROBLEM TO BE SOLVED: To provide a drive circuit for a semiconductor switch element which can shorten the turn on time and turn off time of the semiconductor switch element. SOLUTION: This drive circuit is equipped with a light emitting element 11 which is lit and put out by a pulse power source 12, a solar cell 21 which is optically coupled with the light emitting element 11 and can supply control input to the section between the control input ends of the semiconductor switch element 22, and a photodiode 25 which is optically coupled with the light emitting element 11, with its cathode connected to the positive electrode terminal of the solar cell 21 via a resistor R3 and with its anode connected to the negative electrode terminal of the solar cell 21. An n-channel MOSFET 27a constituting the semiconductor switch connected between both ends of the solar cell 21 becomes off while the light emitting element 11 is lit and becomes on while the light emitting element 11 is put out, with its drain and source connected to the positive electrode terminal and negative electrode terminal, respectively, of the solar cell 21 and with its gate terminal connected to the cathode of the photodiode 25. |
