Charge-based femto-farad capacitance measurement technique for MEMS applications

This paper presents design and simulation of CMOS circuits intended for on-chip differential-mode charge based capacitance measurements in the femto-farad range. The circuits can be integrated with MEMS sensors in CMOS-compatible technology. The reported circuits are characterized by very high sensitivity and a linear C-V response. The performance of differential CBCM circuits using simple current mirrors and novel current-voltage mirrors has also been covered.