Semiconductor integrated circuit and video signal amplification method

Abstract

A semiconductor integrated circuit includes: a charge pumping circuit for generating a negative power supply voltage; an input portion for biasing an average value of an input signal at 0V; and a video signal output portion that operates with a positive/negative power supply utilizing the charge pumping circuit as a negative power supply to amplify the zero-biased signal, outputting signals of positive/negative polarity. A diode clamp circuit is connected to the input portion, and a maximum level of a voltage of the input signal on the negative side is clamped to a clamp voltage produced by the diode clamp circuit when the maximum level of the voltage of the input signal on the negative side is lower than the clamp voltage, thereby suppressing shrinkage of the output signal on the negative side. SYNC shrinkage in the video signal output portion during high luminance signal input is suppressed.

Dependencies are inferred from the claim text.