Patent Number: 6,294,941

Title: Semiconductor integrated circuit including voltage follower circuit

Abstract: A voltage follower and a semiconductor integrated circuit including the voltage follower. In the voltage follower, an output voltage Vout from a source follower output transistor 8 is negative fed back to a gate electrode of the source follower output transistor 8 via a differential amplifier 1. A clamp circuit 28 is provided which clamps the gate potential of the source follower transistor 8 by using a source and backgate potential of the source follower transistor 8, that is, potential at an output terminal 53, as a reference potential. Since the source-gate voltage of the source follower transistor 8 is clamped at a predetermined voltage and thus the maximum electric field applied to the gate oxide film is reduced, it becomes possible to use a MOS transistor having thin gate oxide film and short channel length and having high current drive ability, as a source follower transistor, even when a power supply voltage is high.

Inventors: Yokosawa; Kouji (Tokyo, JP)

Assignee: NEC Corporation

International Classification: G05F 1/10 (20060101); G05F 1/575 (20060101); H03K 005/08 ()

Expiration Date: 09/25/2018