US 2009/0267653 A1 · SEMICONDUCTOR INTEGRATED CIRCUIT DEVICE

Abstract

For a semiconductor integrated circuit device such as AFE including a CDS amplifier, in case of excessive signal input to the CDS amplifier, a technique capable of preventing the response characteristic of the CDS amplifier from deteriorating is provided. In the AFE including the CDS amplifier, the CDS amplifier is prevented from becoming saturated by detecting an excessive signal input and triggering the reset of the CDS amplifier. Thereby, no abnormality occurs in the transient response of the CDS amplifier. Specifically, comparison of input signals to the CDS amplifier is performed by a comparator and the CDS amplifier is reset by a reset circuit (by fixing the input terminals of the CDS amplifier to a constant voltage) in case of excessive signal input, so that the CDS amplifier will not amplify excessive signal inputs.

Claims6

Dependent claims

A semiconductor integrated circuit device comprising:

a CDS amplifier of switched capacitor type with first and second inputs;
a first comparator for comparing a first voltage between the first and second inputs with a second voltage;
and
a first circuit for fixing the first and second inputs of the CDS amplifier to a constant voltage, when the first comparator has decided that the first voltage is larger than the second voltage.

1 more element

Dependencies are inferred from the claim text.

Facts

Application

12/400,827Filed 10 Mar 2009

Priority

JP 2008-11259523 Apr 2008

Published

29 Oct 2009

Term ends

Not estimatedThe source records don’t support an estimate.

Classification4 codes

G11C 27/026
Using a capacitive memory element: associated with an amplifier
H03M 1/129
Sampling or signal conditioning arrangements specially adapted for A/D converters: means for adapting the input signal to the range the converter…
G11C
Static stores
H03M
Coding

Semiconductor integrated circuit device

Life of this patent

Semiconductor integrated circuit device

Life of this patent

Abstract

Claims6