Supercapacitor-Assisted Low-Dropout Regulator Technique for Low Output Ripple DC–DC Conversion

Supercapacitor-assisted low dropout (SCALDO) regulator is an emerging technique to design high-efficiency dc–dc converters based on supercapacitor energy recovery method alongside a low dropout regulator. This very low frequency technique, having low electromagnetic compatibility issues, provides high-efficiency operation applicable to a wide range of output currents varying from a few 100 mA cases with integrated circuit type LDOs to over 100 A cases in the high current discrete form of LDOs. The SCALDO regulator is not a variation of switched capacitor converters due to several definitive reasons. Based on a 12-5 V implementation, this article demonstrates how a SCALDO regulator keeps a very low voltage ripple at the connected dc load while achieving high end-to-end efficiency.