Development of a multi-sensor CMOS ASIC

A multi-sensor application specific integrated circuit has been developed with a number of sensors: capacitive, inductive, magnetic, ambient light, infrared and acceleration. The capacitive sensing is implemented using a unique, patented, charge transfer technique allowing the measurement of very small capacitances while at the same time eliminating the effects of unwanted parasitic capacitances in the measurement circuit. For cost effective implementation the charge transfer measurement circuit has been has been modified, augmented and expanded to not only measure capacitance but also to act as the measurement circuit for all the sensors. Enabling the multi-sensor chip to measure acceleration on a range of MEMs accelerometer chips including a single axis accelerometer, a dual axis xy accelerometer and a z-axis accelerometer, innovative and patent pending techniques have been developed and implemented on standard CMOS. The CMOS ASIC and a MEMs chip will be double bonded in a plastic package offering multi-sensor capability in a small low cost package.