ADAPTIVE BIAS CURRENT GENERATION FOR SWITCHED-CAPACITOR CIRCUITS

摘要

Techniques for adaptively generating bias current for a switched-capacitor circuit are described. The switched-capacitor circuit charges and discharges at least one switching capacitor at a sampling rate and may be aΣΔADC that digitizes an analog signal at the sampling rate and provides digital samples. The switched-capacitor circuit may support multiple modes associated with different sampling rates. A bias circuit generates a bias current for the switched-capacitor circuit to be proportional to the sampling rate for a selected mode, to provide a bandwidth proportional to the sampling rate for an operational transconductance amplifier (OTA) within the switched-capacitor circuit, and to track changes in the switching capacitor(s) due to variations in integrated circuit (IC) process and temperature. The settling time of the switched-capacitor circuit may track with the multiple modes and across IC process and temperature variations.