Sampling switch circuits

Abstract

A sampling switch circuit, including an input node, which receives an input voltage signal to be sampled, a sampling transistor having gate, source and drain terminals, the source terminal connected to the input node, a capacitor, a current source configured to cause a defined current to flow therethrough and switching circuitry configured to alternate between a precharge configuration and an output configuration depending upon a clock signal. In the precharge configuration, the switching circuitry connects the capacitor into a current path between said current source and a first voltage reference node to form a potential difference across the capacitor which is dependent on the defined current. In the output configuration, the switching circuitry connects the capacitor between a second voltage reference node and the gate terminal of the sampling transistor so that a voltage level applied at the gate terminal of the sampling transistor is dependent on the defined current.

Dependencies are inferred from the claim text.