高动态范围多功能快照式红外读出电路设计

设计并验证了一款高动态范围、多种可选功能的32×32红外读出电路。电路在30μm×30μm像元面积内集成了CTIA积分器、采保电路、缓冲器、反饱和功能等,实现了快照式读出。通过积分电容可选,积分时间可从1μs调至33ms(以30Hz帧频计算)的工作方式,有效地扩大系统动态范围,使其具备高低背景工作能力。基于格雷码原理设计的控制电路,实现了动态窗口读出,图像翻转,1、2、4路输出等可选功能。所设计的读出电路采用华虹NEC0.35μmCMOS工艺成功流片,验证了设计的正确性。测试结果表明,电路采用4路输出时,帧频能达到16kFrames/sec,可应用于红外制导领域。

Design of a Very Wide Dynamic Range and Multifunction Snapshot Infrared ROIC

A 32×32 infrared read out circuit (ROIC) with very wide dynamic range and multifunction was presented and verified. Within the area of 30 μm×30 μm,the pixel circuit includes CTIA integrator,sample and hold stage,buffer,and anti-blooming MOSFET. Through the snapshot mode and adjustable integration time from 1 μs to 33 ms (calculated by 30 Hz frame frequency),the dynamic range can be extended efficiently,which provides high and low background operation abilities to the whole system. Based on the Gray code theory,multifunction,such as random window access,dynamic image transposition,and 1,2,4 selectable channel outputs,can be realized by the digital control module of ROIC. The design was successfully manufactured by 0.35 μm CMOS process of Hua-Hong NEC. After the chip test,16 k frames/second can be realized by using 4 channel outputs,and the chip can be used in the field of infrared imaging guidance.