This paper demonstrates a highly reliable active pixel sensor (APS) based on dual-gate (DG) thin-film transistors (TFTs) for high-frame-rate dynamic X-ray medical imaging. By storing the threshold voltage (VT) in the auxiliary gate capacitor and amplifying the voltage signal through the primary gate electrode, the proposed APS circuit compensates for both positive and negative VTshifts of the amplifying TFT. Furthermore, using correlated double sampling by successively subsampling the same pixel without additional memory, the APS circuit eliminates low-frequency noise and DC offset, thereby effectively increasing the dynamic range and the signal-to-noise ratio. The charge-to-current gain of the proposed circuit is 4.50 μA/pC with a nonlinearity of 1.02%. Compared with the conventional 3-T pixel, the proposed APS features a decreased voltage error rate from 23.85% to 0.88% with a VTshift of ±1 V.

In-Sensor computing has emerged as a promising approach for fast, energy-efficient visual perception. This paper presents an in-sensor computing system that leverages amorphous metal oxide thin-film transistors (TFTs) for photo-sensing, computation, and control, enabling rapid and precise visual processing. The system directly computes the first layer of a neural network (NN) during exposure and supports high-resolution raw image readout once a target of interest is detected. The pixel circuit incorporates threshold voltage (VTH) compensation to ensure computational accuracy. Validated on the MNIST dataset, the system achieves 88% classification accuracy with only a 2.2% degradation under a 2V VTHshift. Post-Simulation results show that one computation frame can be finished within 500 ns, demonstrating a 20× speed enhancement over state-of-the-art silicon-based solutions.

This paper presents a highly robust -4V DC-DC converter composed of low-temperature poly-Si oxide (LTPO) TFTs. The proposed circuit significantly reduces the off-state overdrive voltage using the negative voltage bootstrapping technique, thus enhancing the circuit robustness in against VTHshifts for flexible applications. A dual-gate feedback is adopted in the loop control system for a reliable and constant output performance. The post-layout simulation results demonstrate that the steady-state voltage deviation remains below 1%, whereas the conventional design suffers from a voltage degradation of 17.1% for a VTHshift of ±3 V. Furthermore, the compact DC-DC converter achieves maximum power efficiency of 93.7% @20 μA, and 84.1% @100 μA.

This paper presents a capacitive sensing circuit for high-throughput active-matrix (AM) thin-film transistor (TFT) digital microfluidic (DMF) chips, with highly parallel operations to reduce frame time and thereby enhance chip throughput. The proposed circuit integrates a capacitance-to-frequency converter (CFC) into each DMF cell column, enabling simultaneous capacitance sensing and readout of DMF cells in the same row. Furthermore, a pipelined control scheme is devised to parallelize operations across rows, reducing frame time by over 81% compared to conventional DMF chips. Integrated with double-gate (DG) unipolar n-type amorphous indium-gallium-zinc-oxide (a-IGZO) TFTs, the proposed circuit achieves a sensitivity of 13.06 kHz/pF and a resolution of 7.2 fF for a DMF array scale of 150 × 300.