A high efficiency topology for 12 V VRM-push-pull buck and its integrated magnetics implementations

As computer processors move forward quickly, their power management becomes more and more challenging. Nowadays, for the desktop and workstation applications, voltage regulator module (VRM) input voltage has moved to the 12 V output of the silver box. The state of the art 12 V VRM topology is buck. Because of the extreme duty-cycle, buck has a lot of limitations however. This paper presents a high efficiency, fast transient response topology for the 12 V VRM application-push-pull buck (PPB). The push-pull buck has significantly better performance over buck converter. A few integrated magnetics implementations are discussed and tested. Experimental results confirm the theoretical prediction.