Ultra-high sensitivity, low-power dual chopper signal conditioning circuit for integrated sensors

An ultra-high sensitivity, low-power dual chopper amplifier (DCA) for the signal conditioning of capacitive and voltage-mode microelectromechanical systems (MEMS) transducers is presented. The input referred noise and input parasitic capacitance are minimized to increase the sensitivity for femto-Farad range capacitive transducers. The circuit is designed in a 0.13 µm CMOS technology with a 1.2 V supply. The simulated power consumption is 8.4 µW, the gain is 47 dB, and the bandwidth is 10.5 kHz. The input referred capacitance noise floor is 0.0033 aF/√Hz for a 100 fF capacitive sensor.