| 摘要 |
<P>PROBLEM TO BE SOLVED: To suppress an increase in current consumption when limiting a voltage applied between a gate and a source of an nMOS transistor M2 to less than a withstanding voltage. <P>SOLUTION: When a pMOS transistor M1 turns off and the nMOS transistor M2 turns on, a Zener diode ZD2 limits a voltage between the gate terminal and the source terminal of the nMOS transistor M2 to a constant voltage. This can avoid applying a voltage higher than the withstanding voltage between the gate terminal and the source terminal of the nMOS transistor M2. Specifically, a constant current power supply 20b limits a current flowing from a power supply to a ground via the Zener diode ZD2. An nMOS transistor M6b limits a current flowing from the power supply to the gate terminal of the nMOS transistor M2 via transistors M3, M5b, M6b. <P>COPYRIGHT: (C)2013,JPO&INPIT |
