| 摘要 |
PROBLEM TO BE SOLVED: To provide an output circuit capable of reducing a lower limit clamp voltage to a smaller value while keeping an upper limit clamp voltage close to a power supply voltage. SOLUTION: The size of a constant current I4 formed by the constant current source circuit 7 is changed corresponding to an output voltage VOUT by feeding back the output voltage VOU, and when the output voltage VOUT is small, the constant current source circuit 7 is turned OFF to reduce the constant current I4 to zero. Thus, the output voltage VOUT can be reduced to a value close to GND (zero). Thus, the lower limit clamp voltage is prevented from being not lowered by the influence of a filter circuit 9 for high frequency removal, and the lower limit clamp voltage can be reduced to the value close to GND (zero) more than before. COPYRIGHT: (C)2007,JPO&INPIT
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