AN605
Vishay Siliconix
Power MOSFET Basics: Understanding MOSFET Characteristics Associated With The Figure of Merit
Jess Brown, Guy Moxey
INTRODUCTION
Power MOSFETs have bee the standard choice as the main switching device for low-voltage (<200 V) switchmode power-supply (SMPS) converter applications. However using manufacturers’ datasheets to choose or size the correct device for a specific circuit topology is being increasingly difficult. The main criteria for MOSFET selection are the power loss associated with the MOSFET (related to the overall efficiency of the SMPS) and the power-dissipation capability of the MOSFET (related to the maximum junction temperature and thermal performance of the package). This application note focuses on the basic characteristics and understanding of the MOSFET. There are several factors which affect the gate of the MOSFET, and it is necessary to understand the fundamental basis of the device structure before the MOSFET behavior can be explained....
