使用 CMOS-MEMS 製程具數位輸出之電容式微水平感測晶片

Design of Capacitive Micro Tilt Sensor Chip with Digital Output Using CMOS-MEMS Process

張國德(Kuo-Te Chang)

指導教授 ： 許孟烈

國立暨南國際大學/科技學院/電機工程學系/碩士(2012年)

摘要

本論文提出一個微水平感測器晶片的設計，此水平感測器晶片包含一個微流體通道和位於通道兩端的感測電容、感測電容讀取電路和10位元逐漸趨近式類比至數位轉換器(SAR ADC)。注入流體的微流道，在傾斜時因為介電質的流動而改變感測電容值，透過讀取電路將電容值轉換為電壓及放大，並由類比至數位轉換器轉換成數位輸出。
本論文所設計的晶片使用國家晶片系統中心所提供的TSMC 0.18μm 1P6M CMOS-MEMS製程來實現，整體晶片包含PAD面積為1195μm×1196μm。工作電壓操作在0.9V，工作頻率為120kHz，讀取電路在±3.9° 的傾斜範圍有227mV至692mV電壓輸出範圍。SAR ADC取樣率為10kS/s，輸入頻率在58.6Hz時，SNDR為59.086dB、ENOB為9.523-bit。晶片整體功率消耗為1.18μW。

關鍵字

微機電 ； 微流道 ； 水平感測器

並列摘要

In this thesis, the design of a micro tilt sensor chip is presented. The micro tilt sensor is composed of a micro fluidic channel with two sensing capacitors located at oppositive end of the channel, and readout circuit with a 10-bit successive approximation analog to digital converter (SAR ADC). The inclination of the micro channel filled will fluid cause with changes of the sensing capacitance, and the changes can be readout and converted to 10-bit digital output.
The micro tilt sensor chip is implemented using TSMC 0.18μm 1P6M CMOS-MEMS process provided by CIC. The chip area is 1195μm×1196μm. The chip works at 0.9V power supply and 120kHz clock rate. The readout circuit outputs from 227mV to 692mV in the range of ±3.9° inclination. The SAR ADC achieves a SNDR of 59.086dB and ENOB of 9.523-bit under input frequency of 58.6Hz and sampling rate of 10kS/s. The overall power consumption is 1.18μW.

並列關鍵字

CMOS-MEMS ； Micro fluidic channel ； Tilt sensor

參考文獻

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