Process of controlling a switch of a switched-capacitance device, and corresponding switched-capacitance device

Abstract

With a switch including at least one insulated-gate field-effect transistor, an analog input signal is delivered on the source of the transistor and the transistor is controlled on its gate synchronized with a clock signal to successively turn it on and off. On the conclusion of each half-period of the clock signal during which the transistor is off, a precharging capacitor is precharged at the start of the next half-period and for a predetermined precharge duration, with a predetermined precharge voltage. Then, for the remaining duration of the half-period, the precharged capacitor is connected between the source and the gate of the transistor to turn it on under the action of a gate-source voltage which is almost independent of the level of the input signal. At the end of the half-period, the gate of the transistor and the precharging capacitor are grounded.