This paper presents an integrated operational amplifier (OPAMP) consisting of only n-type metal oxide thin-film transistors. In addition to using positive feedback in the input differential pair, a transconductance-enhancement topology is applied to improve the gain of the OPAMP. The OPAMP has a voltage gain (A v) of 29.54 dB over a 3-dB bandwidth of 9.33 kHz at a supply voltage of 15 V. The unity-gain frequency, phase margin (PM), and dc power consumption (P DC) are 180.2 kHz, 21.5 • PM and 5.07 mW, respectively.

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This paper presents a 50 dB high-gain operational amplifier (OPAMP) ,which is fabricated by unipolar n-type indium-zinc-oxide (IZO) thin-film transistors (TFTs). Different positive feedback technologies are employed to achieve sufficient voltage gain. The fabricated OPAMP exhibits an open-loop voltage gain (Av) of 50 dB over a -3 dB bandwidth of 15 kHz at the supply voltage of 20 V. The measured unity-gain frequency (fUG) and the DC power consumption are 500 kHz and 8.07 mW, respectively. In addition, an effective frequency compensation scheme is also introduced and simulated. The simulation results that the proposed OPAMP has a voltage gain of 50 dB with 60° phase margin at 150 kHz unity-gain frequency after compensation.

This paper presents a new gate driver integrated by In-Zn-O thin-film transistors (IZO TFTs) with the etch stop layer (ESL) structure, in which only a single negative power source is used on account of a new boosting module. The boosting module is controlled only by the VIN signal for generating a lower level than VSS. The proposed gate driver with 15 stages is fabricated through the IZO TFT process on a glass substrate to verify its function. The experiment results showed that the proposed gate driver can successfully output full-swing waveforms with resistive load R L = 2 k and capacitive load C L = 30 pF at the 16.7 and 66.7 kHz clock frequencies, and can also output as small as 3.2 μs pulse width with little distortion, revealing good stability.

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