隨著半導體產業的進步，通訊世界也蓬勃發展，如4G通訊技術使得在3G時代無法實現的變成可能。聲音處理方面大家為了講求更高的音質，在醫療中對生理訊號量測更精準的判別微小變化，又或者對於微小的溫度變化進行監控，類比數位轉換器是一個無法被取代掉的部份。本論文設計一個輸入頻寬為20kHz，超取樣率256，取樣頻率10MHz的二階前饋三角積分類比數位轉換器，主要應用於溫度感測，使用交換式電容(Switch Capacitor)實現離散時間系統。整體的架構主要包括放大器(OP)、開關(switch)、比較器(Comparator)等等。經由探討並解決各種非理想效應如放大器有限增益(Gain) 、時脈饋穿(Clock Feedthrough) 、雜訊(noise)等等進行電路上的規格設計。
在經由速度與解析度的取捨，下本論文以TSMC 65nm CMOS 1P9M實現，供應電壓為1.2 V，輸入頻寬為20kHz，超取樣率256，取樣頻率10MHz，得到有效位元數(ENOB)為15.116bits，功率消耗為3.234mW

With the development of the semiconductor industry, the communication world is also booming, 4G technology provide high transmission speed for signal. ADC are an irreplaceable part of the system and it can effectively convert analog signals into digital signals. There are different types of ADCs. This paper designs a second-order feed-forward delta-sigma analog-to-digital converter with a signal bandwidth of 20kHz, an oversampling ratio(OSR) is 256, and a maximum frequency of 10MHz. It is mainly used in temperature sensing and uses switching capacitors (switched capacitors) to implement discrete-time systems. The overall architecture mainly includes OP amplifier, switch, comparator and so on. Touch the switch and solve various non-ideal effects such as gain, clock feedthrough, noise, etc., to design the circuit specifications.
In terms of speed and resolution, this paper is implemented with TSMC 65nm CMOS 1P9M, the supply voltage is 1.2V, the signal bandwidth is 20kHz, oversampling ratio(OSR) is 256, the high frequency is 10MHz, signal to noise ratio SNR>92dB, and ENOB is 15.116 bits. The power consumption is 3.234mW

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