A new approach to reducing output ripple in switched-capacitor-based step-down DC-DC converters

Rapidly dropping power supply voltages and tight voltage regulation requirements for integrated circuits challenge power supply designers. A novel interleaved discharging (ID) approach is presented to reduce the output ripple in step-down switched-capacitor (SC) DC-DC converters. Simulation and experimental results of a four-stage SC DC-DC converter show that the TD approach can reduce the output ripple by a factor of three. The proposed ID approach also improves the converter efficiency by 7%. The ID approach is suitable for all step-down SC DC-DC converters and provides flexibility in design optimization.

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