A New Method For Designing Capacitive Feedback Transresistance Amplifier for Infrared Detector
In order to improve the readout accuracy of infrared detector in infrared imaging technology,where the amplifier circuit is very important.The design of capacitive feedback transimpedance amplifier(CF-TIA)is studied,and a new topology that replaces feedback resistance with the transistor in the feedback loop is proposed.For the proposed topology,the overall frequency response and design pa-rameters such as cutoff frequency and attenuation ratio related to the system stability are proposed and analyzed to obtain the high direct current input dynamic range.Moreover,the addition of additional capacitors to the direct current feedback loop for ensuring system sta-bility is discussed.The excellent agreement between the analyses,simulation and experimental results verify the effectiveness of the pro-posed CF-TIA scheme,and the proposed circuit design has more advantages than the traditional CF-TIA scheme in terms of overall noise performance under normal or low direct current input.Although the circuit is implemented with discrete components,the proposed fre-quency response model and stability analysis are applicable to all CF-TIA applications and CMOS chip designs.
transresistance amplifiercapacitive feedbacktransistordirect current dynamic rangefrequency responsestabilitynoise