陣列光和阻抗感測讀取電路設計之研究

The Research of Readout Circuit Design for Photo and Impedance Sensors Array

高宗碩(Zong-Shuo Gao)

指導教授 ： 孫台平

國立暨南國際大學/科技學院/電機工程學系/碩士(2012年)

https://doi.org/10.6837/NCNU.2012.00273

摘要

本論文研究光陣列感測器讀出電路以應用於阻抗讀出電路之設計，利用原本的光陣列感測讀出電路架構上加入阻抗電路，形成生物感測器阻抗電路的架構；之後再將光陣列感測讀出電路以及生物阻抗感測讀出電路做結合，經由開關的控制既能探測光也能探測生物阻抗。
在陣列讀出電路中的像素電路是採用直接注入式的電路架構，在行共用讀取電路，將訊號提升直流準位、放大、消除及選擇，之後再由輸出緩衝器輸出；因為雙波段的關係，共有兩個輸出緩衝器，分別為長波段及中波段輸出訊號。在整體的陣列感測電路架構上，加上低功率以及電容分享的設計，使其功率消耗比原本的降低27%，以達到了低功率的目的；此外，電容分享使用在直接注入式的電路架構上，將其原本的積分電容值經由開關的控制能夠加大，使得讀出電路能夠適應不同的感測器。阻抗電路設計方面，基本架構主要是陣列感測讀出電路，在原本的直接注入式電路中加上阻抗電路並用開關來控制；而阻抗電路能夠探測的阻抗範圍值約在1kΩ~150kΩ之間成線性且整體電路頻寬為80kHz。
低功率以及電容分享陣列感測讀出電路，使用了TSMC 0.35um 2P4M COM 5V的製程。像素電路的布局面積為30umx30um，但在這個面積內共有兩組直接注入式的電路，分別連接兩個光感測器，而且各自有16x12的陣列，故整體為32x12陣列讀出電路；而輸入的電流範圍在3.3p~10nA，在未有低功率的情形時功率消耗為18.66mw，而有低功率的設計時其功率消耗為13.59mw。
在許多應用上，光陣列感測讀出電路不只僅僅能夠讀取光感測器，只要是電流式感測器都能夠使用，例如溶液濃度的感測，並搭配阻抗電路，在生物醫學探測上一定有著很大的幫助。

關鍵字

低功率 ； 電容分享 ； 雙波段感測 ； 阻抗

並列摘要

This thesis discusses the research of Photo-Array Sensor Read-Out Integrated Circuit (PASROIC) applied in impedance ROIC design. The impedance ROIC is based on the structure of biosensor ROIC increasing the impedance circuit in the primordial PASROIC. Combining the PASROIC with biosensor impedance ROIC, this design is able to detect photo and impedance by switching control.
The structure of direct injection circuit (DI) is used in the pixel circuit of array ROIC. In the row-sharing read circuit, the DC level of signal is raised, and the signal is amplified, eliminated and selected, and then outputted from the output buffer. Two output buffers are designed because of two signal channels, outputting the signal of medium wavelength and long wavelength respectively. By increasing the low power and capacitor sharing design in the structure of array sensor circuit, the power consumption is reduced 27% lower than the previous one, which is achieving the goal of low power. Furthermore, applying the capacitor sharing design in the DI circuit to magnify the integral capacitance by switching control, the ROIC is able to adapt varied sensors. For the impedance circuit design, the basic structure is the array sensor ROIC. By increasing the impedance circuit in the previous DI circuit and control by switch, the impedance circuit is able to detect the impedance between 1kΩ and 150kΩ which is linear with the voltage and the bandwidth of this circuit is 80 kHz.
The low power and capacitor sharing array sensor ROIC adopts TSMC 0.35μm 2P4M COM 5V process. The layout area of pixel circuit is 30μm×30μm, containing two DI circuits which connect two photo sensors respectively. Each DI circuit and photo sensor is an array with 16×12, so the entire ROIC is an array with 32×12. The input current is a range between 3.3pA and 10nA. Without the low power design, the power consumption is 18.66mw; and with the low power design, the power consumption is 13.59mw superiorly.
PASROIC reads not merely the data of photo sensor but also the data of current sensor, so it can be applied in numerous fields, e.g. detection of solution concentration. Collocating PASROIC with impedance circuit, it must be beneficial for biomedicine detection.

並列關鍵字

low power ； capacitor sharing ； dual-band sensor ； impedance

參考文獻

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