A High Dynamic Range Pixel Circuit with High-voltage Protection for 128×128 Linear-mode APD Array

This paper presents a high dynamic range pixel circuit with high-voltage protection for 128×128 Linear-mode avalanche photodiode (LM-APD) array. The pixel circuit includes a high-voltage transistor, a pixel-level analog-to-digital converter (ADC), and a high-voltage protection circuit based on circuit-shared. Through circuit-shared, the pixel-level A/D conversion and high-voltage protection are completed efficiently. Meanwhile, the dynamic range of the entire circuit is greatly improved. The chip is designed in 0.18μm CMOS process. The frame rate is 100Hz and the resolution is 16bit. The simulation results indicate that the dynamic range is 94dB and the power consumption is 5μW per pixel. The pixel pitch is 100μm, which can be reduced further with smaller APD detector.