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

• Main Authors: Zong-Shuo Gao, 高宗碩
• Other Authors: Tai Ping Sun
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/00734731580541421891

博士 === 國立暨南國際大學 === 電機工程學系 === 101 === 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 III 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.