This thesis presents a CMOS readout circuit which for MEMS microphones﹒The readout circuit consists of a charge pump, an impedance transducer and a preamplifier . The charge pump can provide a high voltage for operating microphone through a low power supply voltage﹒The impedance transducer transfers the weak signal from microphone to the input of preamplifier﹒And the preamplifier amplifies the input signal to drive the output load﹒Referring to some related product specifications, a microphone readout circuit chip without the use of external component and additional power supply has been designed and implemented by using TSMC 0.18μm 1P6M CMOS process﹒The chip area is 696×596 μm2 ﹒This circuit operates with 1.8V power supply and the charge pump can provides 12.9V voltage power consumption is 148.87μW﹒