| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overvoltage protection circuit which can protect the internal circuitry reliably against abnormal overvoltage. <P>SOLUTION: An overvoltage protection circuit 2A comprises a rectifier element D10, and switching elements NM<SB POS="POST">1</SB>-NM<SB POS="POST">n</SB>from a first stage to an n-th stage (n is an integer of 2 or more) connected in parallel with each other. The switching elements NM<SB POS="POST">1</SB>-NM<SB POS="POST">n</SB>are provided, respectively, with a first through n-th control ends to which an output voltage from the output end of the rectifier element D10 is applied. Furthermore, each switching element NM<SB POS="POST">1</SB>-NM<SB POS="POST">n</SB>has a controlled end connected, respectively, with a first terminal 3 and a second terminal 4. When an overvoltage is input from the first terminal 3, the rectifier element D10 outputs a control voltage for turning the switching elements NM<SB POS="POST">1</SB>-NM<SB POS="POST">n</SB>on. <P>COPYRIGHT: (C)2012,JPO&INPIT |
