Design of Differential Amplifier with Cross-coupled Connection By Organic TFTs

This work presents the circuit design of an amplifier using organic thin-film transistors (OTFTs). The circuit is constructed based on the common-drain stage incorporating positive feedback. The proposed differential amplifier consists of 8 OTFTs. Negative resistance is introduced to the load of the common-drain differential pair by cross-coupled-connected OTFTs. Simulation results denote a gain (AV) of 22.42 dB with a bandwidth of 551 Hz at a DC supply voltage of 25 V. The phase margin and unity-gain frequency are derived as 67.61° and 7.26 kHz. Our designed organic amplifier demonstrates an overall improved performance while considering both bandwidth and circuit gain, providing the potential design for full organic flexible biosensing application circuits.