Patent ID: 7479811

Claim:
A sample/hold (S/H) circuit module, comprising: a sample/hold circuit, comprising: a capacitor having a first electrode coupled to a fixed voltage and a second electrode coupled to an output node of the sample/hold circuit module; and a sampling switch comprising an output terminal coupled to the second electrode of the capacitor, an input terminal, and a control terminal; a S/H controller, coupled between the control terminal of the sampling switch and a power supply voltage, controlling the sampling switch; a pass transistor comprising a sampling input terminal, an output terminal coupled to the input terminal of the sampling switch, and a control terminal; and a high voltage generator, coupled between the control terminal of the pass transistor and the power supply voltage, providing a voltage exceeding the power supply voltage to the pass transistor such that an input signal of the sample/hold circuit is clamped at a voltage lower than the power supply voltage.