CMOS absolute value precision capacitance measurement system

A switched-capacitor capacitance-to-current converter has been studied and implemented in CMOS technology. It allows the precise measurement of the absolute value of on-chip capacitances, is insensitive to parasitic capacitances to ground, offsets, and charge injection from switches, and can operate up to 500 kHz. The circuit has been integrated together with a test bank of capacitive humidity sensors for their characterization.<<ETX>>