温度传感器是制冷型红外焦平面探测器的重要组成部分, 它用于测量探测器工作温度, 其输出用于制冷机控制, 从而控制探测器温度。探测器的工作温度将直接影响探测器的性能, 如信噪比、探测率和盲元率等。针对传统PN结温度传感器需要模拟信号处理电路及易受电磁干扰的弊端, 设计了一种基于CMOS工艺的集成式数字温度传感器, 可以集成到红外焦平面探测器读出电路中, 直接通过SPI接口输出数字测温值。设计的集成式数字温度传感器采用0.35 μm CMOS工艺流片, 芯片面积为380 μm×500 μm(不包含PAD), 在电源电压2.5 V和采样频率6.1次/s条件下, 功耗为300 μW, 分辨率0.061 6 K。在77 K温度下输出的RMS噪声为0.148 K。测试结果表明, 集成式数字温度传感器可以应用于制冷型红外焦平面探测器温度测量。

The temperature sensor is one of the most important components of the cooled infrared detector assembly which measures and controls the operating temperature of the detector. Its working temperate directly affects the performance of the detector, such as SNR, detectivity and blind pixel rate. Considering that traditional PN junction temperature sensor requires complex analog signal processing and is easily affected by electromagnetic interference, a CMOS integrated digital temperature sensor was proposed. Fabricated in a 0.35 μm CMOS process, the chip area of the sensor is 380 μm×500 μm(without PAD), the proposed sensor reached the conversion speed of 6.1 times/s and consumed 300 μW when the working voltage is 2.5 V. The resolution of the sensor was 0.061 6 K and RMS noise is 0.148 K@77 K. The mesurement results prove that the proposed integrated digital temperature sensor is suitable for cooled infrared detector temperature measurement.