具有超低輸入偏移的40V高動態電壓範圍斬波運算放大器

A 40V High dynamic range Chopper Operational Amplifier with Ultra Low Input Offset

林岳(Yueh Lin)

指導教授 ： 陳中平

共同指導教授 ： 趙昌博(Paul Chao)

國立臺灣大學/電機資訊學院/電子工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202104131

摘要

本文介紹了一個由5V CMOS 和 40V CMOS聯電的 0.5 μm CMOS 工藝實現的具有超低輸入偏移與高動態電壓範圍±20伏特的斬波運算放大器。它實現了在軌到軌輸入輸出共模範圍內（-18.0V至18.0V）內，4 μV的最大輸入偏移、0.02 μV/°C 的最大失調電壓漂移、152 dB 的最小 CMRR、113 dB 的最小 PSRR、13.8 nV/√Hz 的噪訊 PSD 和 1.46 MHz 的單位增益帶寬。透過自動校正反饋（ACFB）的反饋技術可以抑制放大器在低頻中的初始偏移，並避免在輸出端形成波紋。並且在自動校正反饋中使用對稱的被動RC陷波濾波器代替開關電容的陷波濾波器，以減少開關引起的噪訊和偏移，好更加符合高壓的應用中。

關鍵字

超低輸入偏移 ； 高動態電壓範圍 ； 斬波運算放大器 ； 對稱的被動RC陷波濾波器

並列摘要

This thesis presents a chopper op amp with ultra-low input offset and high dynamic range voltage of ±20 volts realized by UMC 0.5 μm CMOS process with 5V CMOS and 40V CMOS transistors. It achieves a maximum input offset of 4 μV, a maximum offset voltage drift of 0.02 μV/°C, a minimum CMRR of 152 dB, a minimum PSRR of 113 dB, 13.8 nV/√Hz noise PSD and 1.46 MHz unity gain bandwidth in the rail-to-rail input and output common mode range (-18.0V to 18.0V). The feedback technology of Auto Correction Feedback (ACFB) can suppress the initial offset of the amplifier at low frequencies and avoid ripples at the output. And in the Auto Correction Feedback, a Passive RC Notch Filter is used instead of the switched capacitor notch filter to reduce the noise and offset caused by the switch, which is more suitable for high-voltage applications.

並列關鍵字

Ultra-low Input Offset ； High Dynamic Range Voltage ； Passive RC Notch Filter

參考文獻

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