Texas Instruments Incorporated
Sample and hold circuit with indefinite holding time

Abstract:

A device includes a capacitive digital to analog converter (CDAC) that further includes a plurality of capacitors to sample an analog input signal. The sampled analog input signal is converted into a digital signal and the digital signal is stored by a successive approximation register (SAR). Thereafter, the SAR regenerates the stored digital signal to a reset plurality of capacitors, and a comparator is configured as an amplifier to generate an equivalent analog voltage of the stored digital signal.