设计了一种二极管型非制冷红外探测器的前端电路，该电路采用Gm-C-OP积分放大器的结构，将探测器输出的微弱电压信号经跨导放大器(OTA)转化为电流信号，再经电容反馈跨阻放大器(CTIA)积分转化为电压信号输出。该OTA采用电流反馈型结构，可以获得比传统OTA更高的线性度和跨导值。输入采用差分结构，可以有效地消除环境温度及制造工艺对探测器输出信号的影响。电路采用0.35 μm CMOS工艺进行设计并流片，5 V电源电压供电。Gm-C-OP积分放大器总面积0.012 6 mm2，当输入差分电压为0~5 mV时，测试结果表明：OTA跨导值与仿真结果保持一致，Gm-C-OP积分放大器可实现对动态输入差分信号到输出电压的线性转化，线性度达97%,输出范围大于2 V。

A front-end circuit for uncooled diode infrared detector, composed of Gm-C-OP integrated amplifier, was designed. The small input voltage steered from diode detector was transferred into current by an operational transconductance amplifier(OTA), and then the current was converted to voltage by a capacitor transimpedance amplifier(CTIA). The OTA used a current feedback loop to achieve higher linearity and transconductance than the traditional one. By adopting differential input structure, Gm-C-OP integrated amplifier can eliminate the effect of ambient temperature and process on the output signal of detectors. The circuit was fabricated in a 0.35 μm CMOS process under 5 V supply voltage. The Gm-C-OP integrated amplifier occupies an area of 0.012 6 mm2. The input differential voltage varied from 0 to 5 mV. Testing results show that the transconductance of OTA is in accordance with the simulation results. The Gm-C-OP integrated amplifier can convert the dynamic small input voltage into a proper voltage linearly and the linearity is 97%. The output range exceeds 2 V.