Research On Readout Circuit Of TEC-free Uncooled Infrared Detector Based On 17?m Pixel

Infrared detection technology has been widely used in both military and civil fields.The appearance of uncooled infrared detection technology is a major breakthrough in the field of infrared detection technology.The uncooled infrared detector uses TEC(Thermo Electric Cooler)to ensure that the infrared detector works at a constant temperature(such as room temperature),compared with the thermal imaging products that need low temperature refrigeration,such as using the Stirling refrigerator,high pressure gas refrigeration or throttling refrigerator.However,TEC accounts for about 80% of the detector's power,and its volume is large.This is at odds with the current market trend of lower power consumption,smaller and more convenient.Therefore,removing TEC to reduce total power consumption and volume has become an important development direction of uncooled infrared detectors.In this paper,we design a TEC-less uncooled infrared focal plane array detector readout circuit based on 17?m × 17?m pixel size 384 × 288 array with on-chip non-uniformity correction function.Based on TSMC 0.18 m 1P6 M process,the design,simulation and analysis of each module in the readout circuit of the uncooled infrared focal plane array were carried out,and the layout design was carried out after the imitation.The main research contents of this paper are as follows:1.Through the analysis of the sources of non-uniformity,and the advantages and disadvantages of the traditional non-uniformity correction methods,and pixel ' s current situation after the removal of TEC,design a new type of non-uniformity correction circuits,and the Skimming work with the Rtrim circuit,be responsible for the rough and fine adjustment of pixel current is carried out to compensate the non-uniformity of pixel current caused by ambient temperature change.2.A new type of positive feedback on-chip temperature sensor is designed.On the basis of PTAT current source,the positive feedback structure of operational amplifier is added to further amplify the weak signal generated by temperature change of the device,and the temperature measurement accuracy is 0.10?/-0.22?.Responsible for measuring the substrate temperature of the system before signal reading and converting it to voltage signal reading for off-chip processing,to provide support for memory reading non-uniformity correction data of corresponding temperature.3.In this paper,a readout circuit for non-TEC uncooled infrared focal plane array detector is designed and simulated.By improving the CTIA circuit structure to improve the integral linearity,a single capacitance sampling/holding circuit using the CDS technology is used to reduce the charge injection effect,and output buffer circuit with MUX structure is used to reuse the same buffer to reduce the power consumption and chip footprint.