應用於生醫系統之低功率軌對軌輸入運算轉導放大器設計

Low Power Rail-to-Rail Input Stage Operational Transconductance Amplifier for Biomedical System Application

潘聖文(sheng-wen pan)

指導教授 ： 洪君維

中原大學/工學院/電子工程研究所/碩士(2009年)

https://doi.org/10.6840/cycu200900427

摘要

近年來積體電路的進步，使得積體電路廣泛應用於生醫系統，因此伴隨發展許多的可攜式與植入式生醫系統。為了確保生醫系統可長時間監測功能，前端電路必須擁有低功率與低電壓條件。前端電路最常建構類比方塊為運算轉導放大器 (OTA)，在低電壓電源的特性下OTA更是需要軌對軌輸入訊號來達到最大的操作範圍。
本研究提出一種低功率、低電壓軌對軌輸入級OTA架構，其電路包含bulk-driven差動對、PMOS差動對、shunt down電路與folded cascode 負載，基於提出電路架構可在低電壓下達到軌對軌輸入範圍，而且不僅避免bulk-driven電路漏電流的產生也可節省功率消耗，模擬OTA操作電源電壓為0.9V，功率消耗為23μW，使用製程為TSMC 0.35μm Mixed Signal 2P4M Polycide 3.3/5V技術。

關鍵字

低電壓 ； 運算轉導放大器 ； 低功率 ； 軌對軌輸入級

並列摘要

The development of integrated circuit (IC) technologies for biomedical system applications has been widely used in recent years. Moreover, it has brought a considerable amount of portable and implantable biomedical equipment. In order to satisfy with ambulatory functions, low power and low voltage has been essential condition for the front-end circuit. Hence, as a basic analog building block, operational transconductance amplifier (OTA) has a limited voltage headroom due to the low battery-voltage characteristics, and it thereby needs rail-to-rail input signal swing to maximize the signal operational range.
The paper present a low-power low-voltage rail-to-rail operational transconductance amplifier (OTA), which combined bulk-driven differential pair, PMOS differential pair, shunt down circuit and folded cascode load. Based on the proposed topology, the low voltage OTA with rail-to-rail input common-mode range is achieved. The scheme not only avoids leakage current of conventional bulk-driven circuit but also reduces power consumption. The simulated power consumption of the OTA is 23μW under conditions of 0.9V supply voltage in TSMC 0.35μm Mixed Signal 2P4M Polycide 3.3/5V technology.

並列關鍵字

Low voltage ； Low power ； Rail-to-rail input stage ； Operational transconductance amplifier

參考文獻

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