← 返回 JSSC 论文列表JSSC 2019第1期Power Management0.18µmEnergy Harvesting
An ULV PWM CMOS Imager With Adaptive- Multiple-Sampling Linear Response, HDR Imaging, and Energy Harvesting Albert Yen-Chih Chiou and Chih-Cheng Hsieh
本文介绍了一种超低电压PWM CMOS图像传感器，适用于物联网和人工智能应用。
0.18-µm CMOS, 0.4V, 60.1 dB PSNR, 141 dB DR
超低电压PWMCMOS图像传感器自适应多次采样高动态范围
▸创新点1：超低电压PWM像素设计（电路创新）。采用0.4V超低电压工作，集成阈值变化消除(TVC)技术，实现+0.36%/-0.29%的非线性度和0.159%的固定模式噪声(FPN)，显著提升低功耗下的成像精度。
▸创新点2：自适应多次采样方案(AMS)（系统创新）。提出像素级自适应多次采样机制，结合4次采样操作将总噪声降低至9.42e-，动态范围达141dB(HDR模式)，兼顾能效与信噪比优化。
▸创新点3：双斜率斜坡参考技术(DSR)（方法创新）。通过创新的双斜率参考电压生成方法，支持n次多重采样，实现60.1dB峰值信噪比(PSNR)的线性响应模式，增强弱光环境下的信号处理能力。
▸创新点4：多模式集成架构（系统创新）。在单芯片中整合HDR成像(141dB)、线性响应(60.1dB PSNR)和能量收集(15.5µW@60klx)三种功能，为IoT/AI应用提供全场景解决方案。
Abstract
This paper presents an ultra-low-voltage (ULV) 300 × 200 pixel pulsewidth-modulation (PWM) CMOS imager with monitoring and capturing for Internet-of-Things (IoT) and artificial intelligent (AI) applications, fabricated in the CMOS 0.18-µm standard process technology. In always- ON monitoring operation, the imager provides high dynamic range (HDR) and energy harvesting (EH) modes for event detection and energy collection, respectively. In low-power image capturing operation, the imager provides a linear-response (LR) mode for object identification and recording. In the LR mode, the proposed ULV PWM pixel with threshold variation cancellation (TVC) achieves a non-linearity of +0.36/−0.29% and a fixed-pattern noise (FPN) of 0.159%. With the proposed pixel-wise adaptive- multiple-sampling (AMS) scheme and the corresponding n-time multiple sampling using dual-slope ramping (DSR) reference, the 0.4-V-operated PWM pixel achieves a total noise of 9.42e − at 4-time AMS operation. The achieved peak signal-to-noise ratio (PSNR) and dynamic range (DR) are 60.1 dB in the LR mode and 141 dB in the HDR mode, respectively, and the harvested power is 15.5 µW at 60 klx in the EH mode.