短波IRFPAs读出电路CTIA输入级的优化设计

CTIA input stage design of short- wavelength staring IRFPAs ROIC

针对凝视短波红外焦平面阵列探测器弱信号耦合读出的难题,设计了一种高注入效率、低噪声、精简结构的运放积分型(CTIA)输入级。该CTIA单元输入级采用电流源负载的共源共栅结构,不仅具有传统CTIA结构的优点,还能克服常规的CTIA结构复杂、功耗过高的缺点。在低温模型的仿真环境下,进行了前仿真和提取版图寄生参数的后仿真。基于CSMC-6S05DPTM 0.5μm工艺流片,CTIA读出电路芯片的测试结果与仿真结果基本一致,输出信号电压范围达到2.5 V,单元功耗小于1.0μW。

To solve the problem of weak signal outputing in short- wavelengh staring IRFPA detector,a CTIA input stage is designed. The input stage has high injection efficiency,low noise and compact structure. A CTIA input stage has cascode structure with current- source load. The novel CTIA can overcome the defects of common CTIA,such as large area and high power dissipation. The simulation and verification are accomplished both before and after completing the layout. The circuit structure is analyzed according to CMOS low- temperature model. The novel CTIA ROIC chip fabricated with CSMC- 6S05DPTM 0. 5μm process technology is measured. The test result is consistent to simulation. The voltage range of output signal reaches 2. 5V and circuit unit power is less than 1. 0μW.