多功能之生醫類比前置電路

A multi-function biomedical analog front end IC

黃瑜婷(Yu-Ting Huang)

指導教授 ： 呂學士

國立臺灣大學/電機資訊學院/電機工程學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.02009

摘要

伴隨著半導體製程技術的進步與成熟，已經能將類比與數位電路結合在一起，並做在同一晶片上。又由於生物醫學上的需求，近幾年來，已成功的利用CMOS技術去結合生物醫學感測器與CMOS電路，實現微小化、低雜訊、低功率、與低成本的單晶生醫晶片。而在生物醫學系統當中，必須先將從感測器進來的類比訊號做優先的處理與調整，所以此論文的目的為，使用TSMC 0.35μm CMOS 2P4M的製程技術來完成多功能之生醫類比前置電路，其主要的三個電路分別為儀測放大器（IA）、二階低通濾波器(two-order LPF)、與一個可程式化增益的放大器（PGA）。
此論文的整個電路架構，是由本實驗室已成功完成的儀測放大器，透過數位控制開關以及回授控制方式來實現可依訊號強度不同做適度放大倍率的電路系統，再藉由低通濾波器濾掉由截波技術所造成的非理想頻率，並經由後端的可程式化增益放大器做進一步的訊號放大。整個系統再藉由開關的處理來達到多功能的設計，使得能夠處理廣大範圍的生物醫學信號，並針對微小的訊號種類（電壓、電流）做適度的調整。整個晶片的面積是1.8x1.35 mm 。在電壓供應為3V下的功率消耗為944.2μW。

關鍵字

類比前置電路

並列摘要

With the advancement and maturation of semiconductor technology, the digital and analog circuit has been integrated on the same chip. In recent years, because of the demand on biomedicine, CMOS bio-sensors have already realized successfully with CMOS technique, achieving miniature, low noise, low power and low cost biomedical systems. In addition, analog front-end circuit with the function of signal arrangement is a critical component in the biomedical system. In this thesis, the main three pieces of circuit are instrumentation amplifier (IA), second-order LPF and a programmable gain amplifier (PGA). They are fabricated in TSMC 0.35μm CMOS 2P4M process.
The first stage of the system is based on IA which had accomplished by our laboratory and through the digital control switch and feedback loop to carry out the circuit system with the function of adjusting different intensity signal. Then, using a two-order LPF ( Sallen-key circuit ) to suppress the spikes from the clock feedthrough and charge injection caused by nonideality of the chopper switches. Finally, the signal is further amplified by programmable gain amplifier in the last stage. In order to let the whole system to deal with a wide range of biomedical signals and attain appropriate adjustment according to different kind of small signal sources, the design relies on a switch on/off devise to achieve these multi-functions. The die area is 1.8mm x 1.35mm and the power consumption is 944.2uW from a 3V voltage supply.

並列關鍵字

analog front end IC

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