Traditionally DC-DC step down converters or Buck converters exhibit better efficiency over a dynamic range of load conditions, comparing to linear regulators. This makes it suitable for wide array of applications. But coming to low load conditions, the losses rises, and overall efficiency reduces. Which makes this non-ideal for low power application and portable designs. This paper investigates the improvement of the low load operation with a new proposed system, comparing to existing methods. The proposed system, targets to transfer the converter to LDO operation when low-load conditions is detected. The inherent advantages like low ripple voltage, zero acoustic noise, improved efficiency is projected with this modification.

Keywords : Buck Converter, LDO, Efficiency, Ripple Voltage, Acoustic Noise