A High Sensitively CMOS Preamplifier for Silicon Microphone

In this paper, a high sensitivity CMOS preamplifier that is specified for the use of silicon microphone is proposed. Testing and measurement the circuit with MEMS microphone sensor device had already done. The high sensitivity circuit is achieved without using the transimpedance source follower. On the other hand, the output signal of the preamplifier will not be degraded and the sensitivity would be increased. The measurement results show that the proposed high sensitivity CMOS preamplifier has better performance in SNR than conventional preamplifiers. The circuit is realized in TSMC 0.35 mum CMOS technology and consumed 1.4 mW under a plusmn2.5 V power supply. The core size is 55times60 um²