Introduction

The FDMF6704 DrMOS MCM (Multi Chip Module) product has HS and LS FETs and a gate driver all contained within a single module. The design has been optimized for Synchronous Buck applications. The switching and conduction loss of each HS FET, LS FET and gate driver are critical for system and application design. Generally it is hard to get measurement of each internal loss because of its MCM structure. Instead of measuring each power loss elements, expression of module power loss have been used to show MCM product power related performance. Module power loss is defined to be all power losses dissipated by DrMOS module itself. It includes all HS FET, LS FET and gate driver power losses. Using this approach, a system designer can easily estimate total power loss of the system, and do easy and convenient predictions of design related application performance. This application note explains basic theory of module power loss, and how to use the module power loss calculation tool. It is easy and convenient to use the power loss calculator when the system designer does a particular application design.