• Microelectronics
  • Vol. 55, Issue 1, 99 (2025)
ZHANG Rui1,2, ZHEN Shaowei2,3, LIU Yang1,2, LI Yanliang4..., ZHANG Jianing4, LI Yikang4, OU Yi4 and ZHANG Bo3|Show fewer author(s)
Author Affiliations
  • 1College of Electronics Engineering/International Semiconductor College, Chongqing University of Posts and Telecommunications, Chongqing 400065, P. R. China
  • 2Chongqing Institute Microelectronics Industry Technology, Univ. of Elec. Sci. and Technol. Of China, Chongqing 401331, P. R. China
  • 3State Key Lab, of Elec. Thin Films and Integr. Dev., Univ. of Elec. Sci. and Technol. of China, Chengdu 610054, P. R. China
  • 4The 44th Research Institute of China Electronics Technology Group Corporation, Chongqing 401331, P. R. China
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    DOI: 10.13911/j.cnki.1004-3365.230502 Cite this Article
    ZHANG Rui, ZHEN Shaowei, LIU Yang, LI Yanliang, ZHANG Jianing, LI Yikang, OU Yi, ZHANG Bo. Design of Isolation Error Amplifier for Switching Power Supply[J]. Microelectronics, 2025, 55(1): 99 Copy Citation Text show less

    Abstract

    A switching power supply can be classified as either an isolated or non-isolated power supply, based on the presence of electrical isolation. An isolated power supply uses devices in the power transmission and signal feedback paths to provide electrical isolation, thereby protecting against ground loops and power supply failures. Traditional isolated power supplies utilize linear optocouplers, which face limitations such as limited bandwidth and aging. To address these issues, this paper proposes the design of an isolation error amplifier based on a high-voltage capacitor to close the isolation feedback loop. PWM and OOK modulation are used to enable analog signal transmission across the isolation barrier, offering the advantages of high integration and CMTI. The operational principles of the proposed isolation error amplifier and the modulation/demodulation process are analyzed in detail. The proposed chip is designed using a 0.18 μm BCD process. Simulation results demonstrate that the isolation error amplifier can support error voltage transmission of 1x and 2.6x when the output voltage of the isolated power supply is between 4 and 40 V, which is used to drive the PWM controller.
    ZHANG Rui, ZHEN Shaowei, LIU Yang, LI Yanliang, ZHANG Jianing, LI Yikang, OU Yi, ZHANG Bo. Design of Isolation Error Amplifier for Switching Power Supply[J]. Microelectronics, 2025, 55(1): 99
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