Design And Realization Of Roic Based On CTIA

Infrared Focal Plane Array is the important photo-electronic device to capture infrared radiation information, which is composed of Infrared Detectors array and Readout circuit array. The performance of the Readout circuit affect directly the performance of the Infrared Focal Plane Array. The high performance Readout circuit is the key to guarantee normal working of Infrared Focal Plane Array.In this paper, design and accomplish 16×16 Readout circuit array with Capacitive transimpedance amplifier. The Readout circuit includes six modules: Capacitive trans-impedance amplifier input circuit, dark current restraint circuit, correlated double sampling circuit, bias voltage control circuit, and digital control circuit. By analyzing principle of each module, determine primarily circuital structure and related device parameters. Then analyze deeply circuital function and performance with spice simulation and consider comprehensively other factors to accomplish design of Readout circuit structure based on the Quantum well infrared photo detector. On this basis, design layout and connection each module with 0.35μm digital and analogy mixed signal CMOS process and full costumed design method. Then verify validity of layout by post-simulation, and finally tape-out. The size of 16×16 array is 1mm×1mm. After tape-out, self-design and make PCB test circuit and provide control signal with FPGA to accomplish chip test. The test result shows that the bias-voltage of the ROIC is adjustable between 0 and 2 voltage, and frame rate of the ROIC is 10KHz. When the dark current is hundreds of nA, the Readout circuit can obtain about ten nA optical current. So the function of chip accord with design requirements.