Design And Application Of Integrated Processing Circuit For Ultra-long Linear Array Infrared Focal Plane Detector

High-resolution infrared remote sensing is a research hotspot in recent years,and also an important means to detect and identify targets in the field of space remote sensing.More and more infrared remote sensing instruments with high ground resolution,high radiation sensitivity and short revisit period are urgently needed.The wide field-of-view infrared push-scan camera is the inevitable choice.In addition to the requirement for a large-aperture optical system,a large-scale,long-line array infrared focal plane array detector is also needed,thus the same-scale information acquisition and processing circuit is needed.This is bound to result in a huge demand for system resources,and space remote sensing instruments form a contradiction of resource constraints.In order to solve this problem,an information acquisition and processing circuit is designed and developed based on the research of an infrared camera with a super-largescale infrared focal plane detector.An integrated analog processing chip LHB760 with four signal conditioning functions has been developed by using an operational amplifier bare chip and peripheral resistors and capacitors.Signal input interfaces for different types of D/A converters and LPF terminals are available.Through the simulation and test of its bandwidth,power consumption,noise and other electrical performance,it is proved that it can save system resources to a certain extent while guaranteeing the performance of conventional circuit.Combined with the development goal of infrared camera,the application of LHB760 in information acquisition and processing circuit is described in this paper.Taking LHB760 as the core,an information acquisition circuit for an ultra-long-line infrared focal plane array detector with 33000 pixels is developed.Taking FPGA as the core,the detector's working sequence,multiplexer gating control,the control of the detector's power supply chip and the digital devices of the information processing circuit are designed,and the parallel data after A/D conversion is converted into serial data.The LVDS chip transmits the serial data to the back-end information processing circuit,thus completes the entire process of the detector data acquisition,conversion and transmission.The performance of the information acquisition and processing circuit is verified by obtaining the clear image data of the long-range target through the infrared imaging experiment.The dynamic range and the NETD of infrared camera in different working modes are tested and verified.The dynamic range of infrared camera in different working states can reach 324K?415K.The NETD is better than 50 mK in many different circuit working states,which can meet the development goal and further verify the rationality of the design of the information acquisition and processing circuit.