壓電式壓力感測器訊號處理電路之設計與分析

A Study On Signal Processing Circuits Of Piezoelectric Pressure Sensors

指導教授 : 黃榮堂    研究生 : 林大為  機電整合研究所 88年


摘要

壓電材質鋯鈦酸鉛(PZT)一直是感測器中感測端的重要元件,其壓電的特殊特性也造成了後端處理電路的複雜性。而電子電路的訊號處理方式可分為兩種,一種是電壓模式(Voltage-Mode);另一種是電流模式(Current-Mode)。前者如OP放大器(Operational Amplifier),後者如電流傳輸器(Current Conveyor)和電流運算放大器(Current Operational Amplifier)。
而處理壓電特性的訊號處理電路-電荷放大器(Charge Amplifier),大都是採用前者電壓式的處理方法。本論文除了驗證電壓式處理單元之外,並且也提出了一個利用電流式處理壓電訊號的可能性。電壓式的訊號處理電路和電流式的單一元件設計部分,已經由TANNER TOOLS PC版的設計、模擬和佈局,並利用工作站版的Dracula驗證無誤後送交國科會晶片中心製作,其製程是UMC2P2M(聯華電子公司0.5um Double Poly Double Metal)。而電流式的訊號處理電路部分,則已經利用TSPICE設計與模擬並驗證其在低雜訊、低功率、高頻寬的特性。

關鍵詞:電荷放大器、電流傳輸器、電流運算放大器、訊號處理

ABSTRACT

Lead-zirconate-titanate (PZT) is a very important component of force-sensing device, but it's piezoelectric characteristics may cause the complicacy of the readout processing circuits. The signal processing methods of the electrical circuits can be divided into two species. One is the voltage-mode circuit, and the other is the current-mode. The first one is based on an operational amplifier, and the last one can be based on a current conveyor or a current operational amplifier.
The voltage-mode circuit adopted in this study is focus on the charge amplifiers. Besides, we also proposed a new method to process the sensing signal by using the current-mode circuits. The voltage-mode signal processing circuits and the current-mode device are fabricated by CIC with the UMC052p2m design rules after the procedures of design, simulation, layout, and design rules check by using Tanner Tools and Dracula. The current-mode signal processing circuits are also verified in terms of some characteristics of low-noise, low-power, and high-bandwidth by using the Tspice's simulation.

Keyword:Charge Amplifier、Current Conveyor、Current Operational Amplifier、Signal Processing.. 2