Research On Readout Circuit Characteristics Of Focal Plane Array For Hyperspectral Applications

Featuring many advantages such as excellent adaptability for environment,strong ability for detecting camouflage targets,low power consumption and small size,infrared detection is widely used in various fields.Readout circuit is a crucial part in infrared detection system,which is worth researching.With the improvement of material,devices and technology in infrared detection field,as well as market demanding,readout circuit is rapidly heading forward larger arrays,quicker speed,lower power consumption and smarter.The digital control is a significant part to improve the performance of readout circuit.The readout circuit for ultra-spectral application has a relatively high dynamic range and requires function of controllable gain.Integral capacitance is a significant parameter which determines the gain of readout circuit.By choosing different capacitance,we can control the gain of all rows of readout circuit.In addition,when it comes to readout-circuit design with higher performance,dynamic windowing is a quite useful function in increasing frame rate and checking bad point for large array applications.The dynamic image transposition function makes the readout circuit able to fit different optical system.Multi-channel readout can efficiently increase frame rate.?.This thesis states the research on control bus of integrating,readout,reset.Based on the research,this thesis implemented the whole architecture of readout circuit,including controllable gain readout circuit with reading while integrating mode,dynamic windowing function,dynamic window transposition and multi-channel readout.The input module of proposed design can register the control bits of gain and multiple functions.The design covers the row control module and column control module,which can be controlled by the control bits of input register,implementing controllable gain and multi-function readout circuit.?.Because the readout circuit demands larger array,higher speed,lower power and more intelligent,the traditional way of shifting register becomes incapable for controlling readout circuit.The semi-custom applied to digital control of readout circuit is studied in this thesis.The whole process is completed.The first step is dividing different function module,after which is coding in HDL.The platform is implemented for simulation and verification.In physical design,the PAD design and output port layout are completed.The whole design establishes an overall layout scheme that matches the digital part and analog part of readout circuit.The design completed the layout,synthesis for clock tree,routing and other processes.The final analysis report and verification report of this design shows that the area plan meets the layout requirement of analog array,the power consumption is about 14.82 m W and circuit's function is right.?.The essence of the digital control of the readout circuit lies in addressing.The addressing counter is the main source of power consumption for the digital control of the readout circuit.The Gray code has the feature that only one bit is flipped at a time.In theoretical analysis,it has higher addressing stability and lower switching power consumption.An addressing counter that increments and decrements according to the Gray code method is designed.It is preliminarily applied to the implementation of dynamic windowing and readout sequence reversing.The power analysis results show that the Gray code addressing counter reduces the power consumption by 50%-60%compared with the binary addressing counter.