IEEE MWSCAS'06: PROCEEDINGS OF THE 2006 49TH MIDWEST SYMPOSIUM ON CIRCUITS AND SYSTEMS, VOL II
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2006年
关键词:
D O I:
暂无
中图分类号:
TM [电工技术];
TN [电子技术、通信技术];
学科分类号:
0808 ;
0809 ;
摘要:
This paper reports a low-noise low-power amplifier design that is suitable for CMOS-MEMS capacitive vibratory gyroscopes. Low noise is achieved by chopping the Coriolis signal to a high frequency (1 MHz) and optimally sizing the input transistors. Low power consumption is obtained by applying a fully differential, two-stage open-loop architecture, which utilizes low-impedance node chopping and dynamic element matching. Pseudo-resistor MOS-Bipolar devices are used to establish a stable de bias at the sensing electrodes. A prototype was fabricated in a TSMC 0.18 mu m CMOS process. When chopped at I MHz, the circuit achieves a gain of 40 dB. The equivalent input noise is 20 nV/root Hz for frequencies up to 20 kHz. The equivalent circuit offset is below 200 mu V. With a 3.3 V supply voltage, the circuit draws a current of 300 mu A.