WORKSHOP PAPER
A Digital Pixel Sensor with 0.17%/-0.32% Non-Linearity and 75.3μW Power Consumption Using Wide-Swing PWM and Embedded 10-bit 3T-GC-eDRAM
Cheng-Jhe Li1, Guan-Cheng Chen1, Chih-Cheng Hsieh1
1National Tsing Hua University, Hsinchu, Taiwan

Abstract

This paper introduces a digital pixel sensor (DPS) using wide-swing pulse-width modulation (PWM) with high linearity, low power consumption, and embedded 10-bit pixel-level storage units. The photo-generated signal, after exposure, is converted into a corresponding pulse width using PWM operation, which then latches the code from a global counter and stores it in the embedded 10-bit memory. This process enables parallel analog-to-digital conversion within the pixel array, thereby reducing noise and improving signal fidelity. The optimized embedded 3T-GC-eDRAM memory architecture, compared to 1T1C eDRAM, offers enhanced data retention and signal integrity through increased storage capacitance and amplified readout charge flow while consuming less power. The sensor is fabricated using TSMC standard 180nm 1P6M CMOS technology, with a pixel pitch of 15 μm and a total area of 2700 × 2700 μm². It operates at a supply voltage of 1.5V/1.2V and a frame rate of 181.8 fps, achieving a low non-linearity of 0.17%/-0.32%, a high linear range of 0.9V, and the imaging Figure of Merit (iFoM) of 25.3 pJ/pixel·frame.
Year: 2025
Workshop: IISW
URL: https://doi.org/10.60928/a6uk-9un0
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Keywords

Digital Pixel Sensor, Non-Linearity, Power Consumption, Wide-Swing PWM, Embedded 10-bit 3T-GC-eDRAM,

References

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