| 摘要 |
PROBLEM TO BE SOLVED: To form a protection circuit by using transistors having a lower withstand voltage than a power-supply voltage.SOLUTION: A protection circuit 1 includes: two or more N short-circuit switches 81 and 82 connected in series to each other that form a short-circuit circuit short-circuiting between a first power-supply terminal and a second power supply terminal; a bias circuit maintaining a voltage at an intermediate node with an intermediate node voltage having a value between a first power-supply voltage and a second power-supply voltage, and opening the short-circuit circuit by turning off at least one short-circuit switch of at least two short-circuit switches when the first power-supply voltage is supplied to the first power-supply terminal and the second power-supply voltage different from the first power-supply voltage is supplied to the second power-supply terminal; and an RC trigger circuit 31 short-circuiting the short-circuit circuit by turning on all the N short-circuit switches while a current surge is applied to the first power-supply terminal. |
