Low-Power Switched Operational Amplifier Using a-InGaZnO TFTs

  • Suprateek ShuklaEmail author
  • Bhawna Tiwari
  • Nishtha Wadhwa
  • Pydi Ganga Bahubalindruni
  • Pedro Barquinha
Conference paper
Part of the Communications in Computer and Information Science book series (CCIS, volume 892)


This paper proposes a novel low-power operational amplifier (OPAMP) using amorphous indium-gallium-zinc-oxide thin-film transistors (a-IGZO TFTs). By introducing dynamic operation, power consumption of the proposed OPAMP has been significantly reduced without compromising with other design parameters like gain, slew rate etc. In addition, common mode feedback (CMFB) and internal frequency compensation have been used to ensure good common mode rejection ratio (CMRR) and stability of the OPAMP, respectively. In order to demonstrate the proposed idea, low power OPAMP is designed and simulated using in-house a-IGZO TFT model in Cadence Virtuoso. Circuit simulations have been carried out at a supply voltage and device channel length of 10 V and 20 \(\upmu \)m, respectively. From simulations, a gain of 30 dB and unity gain bandwidth of 106.8 kHz with a phase margin of 63\(^{\circ }\) were noticed. The power consumed by the proposed OPAMP is 146.8 \(\upmu \)W, which is significantly lower compared to the OPAMPs implemented with various TFT technologies. The proposed OPAMP circuit would find potential applications in various real-world large area applications that need flexible electronics with low-power consumption like bio-medical and wearable devices.


TFT a-IGZO TFT Low-power design OPAMP CMFB CMRR 



This work is supported by early career research grant with project ref. ECR/2017/000931. The publication is an outcome of the R&D work undertaken project under the Visvesvaraya PhD Scheme of Ministry of Electronics & Information Technology, Government of India, being implemented by Digital India Corporation.


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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  • Suprateek Shukla
    • 1
    Email author
  • Bhawna Tiwari
    • 1
  • Nishtha Wadhwa
    • 1
  • Pydi Ganga Bahubalindruni
    • 1
  • Pedro Barquinha
    • 2
  1. 1.Department of Electronics and Communication EngineeringIndraprastha Institute of Information TechnologyNew DelhiIndia
  2. 2.CENIMAT/I3N, Departamento de Ciência dos MateriaisFaculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa and CEMOPUNINOVACaparicaPortugal

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