隨著老年化時代的來臨以及各種文明病的出現，現代人越來越注重自己的身體監控，各種穿戴式血壓血糖心跳感測器應運而生。由於穿戴式的感測器通常需長時間的配戴，因此輕巧及省電為主要考量。一般生理訊號量測系統可分為感測與後端處理，而後端處理可藉由積體電路實現進而縮小整體系統面積。
本論文為設計一個適用於生理訊號量測的類比數位轉換器(Analog to Digital Converter, ADC)，使用連續時間三角積分調變器(Continuous Time Delta-Sigma Modulator, CTDSM)實現，架構為三階積分器與一位元量化器。此ADC能處理常見的生理訊號並具有足夠的解析度，完整地將前端低雜訊放大器處理過後的訊號轉換為數位資料。另外CTDSM具有隱性抗交疊濾波器(Anti-Aliasing Filter, AAF)的特性，在系統上可以省去或減緩前級AAF的使用進而省下一些功耗。在相同積分電容下，比起離散時間，連續時間積分器可以使用較小功耗達到規格要求。而一位元量化器擁有最好的線性度並可降低電路的複雜度。
本次晶片實現使用台積電0.18 um CMOS 1P6M製程，晶片大小為0.8483 mm2。在頻寬為10 KHz下，其輸入動態範圍為88 dB、有效解析度位元(ENOB)為12.6 bits、超取樣率為64。在1.8 V電源供應下，整體晶片功耗為140 uW。

With the coming of aging societies and the emergence of civilized illness, modern people increasingly focus on their body monitoring, so that various wearable devices of blood pressure, blood glucose and heart rate sensors have been launched. However, it usually be worn for long periods of time, so the lightweight and higher power efficiency are the key factors in considering. In general, biosignal detection system can be classified as sensor and the back-end processing circuit. The back-end processing circuit may be implemented by the integrated circuit (IC) to minimize the area.
This thesis designs an analog to digital converter (ADC) for biosignal applications and implemented by continuous time delta-sigma modulator (CTDSM). The structure of the modulator is a third-order integrator and single bit quantizer. This ADC could process common biosignals and has enough resolutions to convert the analog signals to digital signals completely. In addition, the CTDSM also has the important property of implicit anti-aliasing filter (AAF), and it can relax the AAF front end and reduce power consumption in full system. Comparing to discrete time, the continuous time integrator can have lower power consumption to achieve the specification if both of them have the same type of integrator capacitor. In the end, the single bit quantizer can provide the best linearity and reduce the complexity of the circuit.
The chip was implemented in 0.18 um CMOS technology and the core size is 0.8483 mm2. This work achieves 86 dB dynamic range and 12.6 bits ENOB in 10 kHz signal bandwidth with an oversampling ratio of 64. The power consumption is 140 uW under 1.8 V supply voltage.

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