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| The Analysis of Digital Control Approach to Improve Light-Load Efficiency for Buck Converters with Synchronous Rectification |
| Xu Yang |
| Department of Electrical Engineering, Tongji University, Shanghai 201804 |
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Abstract A digital control scheme is proposed to improve the light-load efficiency for Buck converters with synchronous rectification. The method adopts a fixed switching frequency at heavy load, and smoothly switches to constant on-time control mode at light load for the purpose of reducing the switching losses. In addition, different from traditional control methods, the proposed approach dynamically estimates the inductor current zero crossing point accurately based on on-time of the drive signal and inductor volt-second balance to force converters work in discontinuous conduction mode, which significantly reduces conduction losses at light loads. These features ensure the converters own higher efficiency over a wide load range. Theoretical analysis and experimental results are provided to verify the proposed scheme.
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Published: 24 February 2017
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| Cite this article: |
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Xu Yang. The Analysis of Digital Control Approach to Improve Light-Load Efficiency for Buck Converters with Synchronous Rectification[J]. Electrical Engineering, 2017, 18(2): 14-19.
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| URL: |
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http://dqjs.cesmedia.cn/EN/Y2017/V18/I2/14
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2017, Vol. 18 
