| 摘要 |
[TASKS] To provide a buffer circuit which is driven with a low voltage and operates in a high speed. [COUNTERMEASURE] The present invention is provided with a first comparator in which a comparing portion is constituted by one of P channel and N channel MOS transistors provided between an input terminal and an output terminal of a buffer amplifier and a predetermined offset voltage is set for the comparing operation in the comparing portion, and a switch circuit which turns ON/OFF in response to an output signal from the first comparator, wherein a leading up of an output voltage from the buffer amplifier is accelerated by flowing current from a power source line to the output terminal, the buffer circuit further provided with a second comparator of which comparing portion is constituted by the other of P channel and N channel MOS transistors and an operation restricting circuit for restricting the comparing operation of the second comparator in a range of a dead band of the transistors constituting the comparing portion of the first comparator, wherein the switch circuit is turned ON/OFF in response to the output signal of the first comparator and the output signal of the second comparator.
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