| 摘要 |
<P>PROBLEM TO BE SOLVED: To ensure a stepwise chevron-shaped characteristics that do not cross a load rule, in a constant-voltage circuit equipped with an over current protection circuit that has the stepwise chevron-shaped characteristics. Ž<P>SOLUTION: A constant-voltage circuit includes a restriction voltage setting circuit 5, which generates a voltage for turning off the corresponding NMOS transistors M11, M10 and inputs the voltage to the gate, when an output from an output terminal reaches first and second limit voltages. This restriction voltage setting circuit 5 is equipped with a PMOS transistor M22; a depletion-type NMOS transistor M24; a PMOS transistor M23 constituting a current mirror circuit together with an M22; a depletion type NMOS transistor M25; and an inverter INV1, connected between the drain of M25 and the gate of M10. The first and second limiting voltages are set with offsets due with respect to the size of M25 to M24, or offset due with respect to size of M23 to M22. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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