P‐128: Distinguished Poster: A 1.33 μV/e⁻ Voltage Mode Active Pixel Sensor with Threshold Voltage Compensation for Dynamic X‐Ray Imaging

This paper proposes a high‐gain voltage‐mode active pixel sensor (V‐APS) for high‐frame‐rate dynamic X‐ray imaging. Due to a source‐follower structure, the proposed active pixel circuit exhibits superior linearity compared to current‐mode APS. And, a shared programmable gain amplifier (PGA) is employed to provide secondary‐stage amplification, mitigating the gain limitation of the source‐follower structure. The charge‐to‐voltage gain of the proposed V‐APS achieves 1.33 μV/e − with a nonlinearity of 0.38%. Furthermore, VT variation and shift of amplifying transistors in pixels and PGAs can be compensated by using dual‐gate thin‐film transistor technology. In comparison with conventional 3‐T V‐APS, the proposed one features a significant decrease of output voltage error rate from 43.67% to 0.79% at a VT shift of ±0.5 V.