基於CMOS-MEMS 共振式開關之無線電喚醒接收機

Abstract

本論文研究為基於微機電共振式開關結合CMOS邏輯電路的低功耗特點，開發近零待機功耗的喚醒接收器系統。委託國家晶片中心在CMOS-MEMS 0.35µm 2P4M製程平台下整合無線接收器前端以及後端電路，並在國立臺灣大學工學院奈米機電系統研究中心進行晶片的後處理，包括濕蝕刻懸浮製程以及對晶片的初步測試如: 探針式表面分析(Probe-Type Surface Analysis)。由於共振式接收器前端利用共振特性使結構撞擊輸出端並短路，在平時未發生共振現象時是斷路狀態因此不會有電流導通，表現近零功耗的特性。 共振開關以OOK方式調變訊號結合後端的包絡檢測器(Envelope Detector)以及數位檢測器(Digital Detector)進行訊號處理，將解調完的數位邏輯電位"0"與"1"輸入相關器電路中以CMOS邏輯電路完成與密碼本(Codebook)的比對，具有輸入阻抗高、功耗低、抗干擾能力強等優點，只靠閘極電壓控制電路，不需要電流傳遞訊號。微機電共振式接收器前端在工作模式下完成解調工作所需的平均功耗為4.81 μW，完成輸入訊號與密碼本之間的比對並輸出喚醒訊號的平均功耗僅0.743 μW。

This thesis presents a wake-up receiver system with near zero standby power con-sumption, through MEMS resoswitch-embedded receiver frontend and the low power consumption of CMOS logic gate. The chip fabrication was supported by Taiwan Sem-iconductor Research Institute (TSRI) and realized on a 0.35-μm 2poly-4-metal CMOS-MEMS platform. The post-fabrication and test are executed at NEMS Research Center at NTU such as the post-metal-release process and the probe-type surface analy-sis. Since the resoswitch-embedded communication frontend uses the resonance nature to make the structure impact the output electrode end and short circuit, the open circuit when no resonance occurs, so there is no current consumption, exhibited the advantage of near-zero standby power consumption. The resoswitch applying OOK demodulated input signal, combined with the back-end envelope detector and digital detector for signal processing. Input the demod-ulated digital bits "0" and "1" into the correlator circuit to compare with the codebook with the CMOS logic circuit. It has the advantages of high input impedance, low power consumption, and strong anti-interference ability. Only rely on the gate voltage to con-trol the circuit operation, with no current consumption during data transmission. The av-erage power consumption of the resoswitch-embedded communication frontend that completes the demodulation work in the active mode is only 4.81 μW, and the average power consumption for completing the comparison between the input signal and the codebook and outputting a wake-up signal is only 0.743 μW.