Improve light load efficiency for synchronous rectifier buck converter

A DC/DC converter with high efficiency over very wide load range is necessary for many low voltage applications, such as battery supplied systems and microprocessor power supplies-voltage regulator module (VRM). In order to improve the efficiency of low-voltage power converters, synchronous rectifier technology is widely used. The disadvantage of this technology is low efficiency at light load. This paper proposes a new technology that can improve light load efficiency with very simple implementation. Since current sensors are not required, high density and high efficiency can be achieved that makes the whole circuit suitable for integration. In the paper, two application examples are given. Experimental results verified that this technology significantly improves synchronous rectifier buck converters light load efficiency.