Bootstrapping techniques for floating switches in switched-capacitor circuits

Bootstrapping techniques improve the linearity of switched-capacitor circuits, especially for low supply voltage. This paper proposes simple but effective techniques for bootstrapping floating switches. The method is applicable to such fundamental circuits as sample-and-hold (S/H) stages, switched-capacitor (SC) filters and SC amplifiers. It can make the on-resistance and channel charge of the switches independent of the signal, and hence enables linear operation even for low bias voltages.