Renesas Technology Corp.

Hitachi Tohbu Semiconductor, Ltd.

Other

Hitachi Ulsi Systems Co., Ltd.

Hiroki Nakajima

Tatsuji Matsuura

Eiki Imaizumi

Yasutoshi Aibara

Masumi Kasahara

Kouichi Yahagi

An AD-converted digital video data is encoded by a difference encoding method before it is outputted and such encoded digital video data is then outputted, after it is converted to gray code or to a predetermined code in which a fixed value is added. Problems solved include noise that is generated when the AD conversion circuit outputs video data and that migrates into a CCD side via a power supply line on a printed circuit board, and noise that appears on a display image by migration into an input terminal side from an output circuit side via the power supply line and a semiconductor substrate within an AD conversion LSI.

Semiconductor integrated circuit device and imaging system

An image input system includes a solid state image pickup device and a preprocessor for performing correlated double sampling amplification on an output of the image pickup device and outputting a video signal. The preprocessor has a correlated double sampling amplifier for outputting signal information corresponding to a difference voltage between the black level in a feedthrough period of the image pickup device and a signal level in a charge signal output period; and an offset cancelling circuit for cancelling an offset voltage corresponding to the difference voltage in a state where the image pickup device is optically interrupted to the input terminal of the correlated double sampling amplifier. The correlated double sampling amplifier cancels out the offset voltage and the offset cancelling voltage as signal components of polarities opposite to each other, so that circuits following the correlated double sampling amplifier are not influenced by the offset voltage.

Image input system

In an imaging system having a semiconductor integrated circuit device, noise problems due to a large through-current in an output circuit resulting from the change-over of digital video data outputted from an AD conversion LSI are reduced by a technique involving encoding and code conversion. After AD conversion of an analog color video signal from an imaging element, a difference between codes of adjacent pixels is obtained in regard to the same color, and an output code of this difference is converted into a code with less change-over bits between the adjacent codes.

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Maebashi, Japan

Hiroki Nakajima