摘要 |
A semiconductor switch of a PNPN structure comprises a PNPN switch of an equivalently four-layered structure including a P-type anode, N-type cathode, N-type gate and P-type gate, a first NPN transistor, a second PNP transistor, a level shifting circuit, and an impedance element, wherein the impedance element is connected between the collector and emitter of the first transistor, the first transistor has its collector and emitter connected to the P-type gate and N-type cathode respectively, and the second transistor has its emitter and base connected to the P-type anode and N-type gate, respectively, and has its collector connected to the base of the first transistor through the level shifting circuit. In this arrangement, the first transistor is driven by the current flowing through a PN junction at the end on the side of the anode of the PNPN switch and the level shifting circuit, so that the semiconductor switch has a great dv/dt withstanding power, operates with high sensitivity, has a high breakdown voltage in both directions and facilitates the setting of circuit constants.
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