AN4191 Datasheet, PDF (1/20 Pages) STMicroelectronics – This report shows the analysis performed on Power MOSFET devices

AN4191
Application note
Power MOSFET:
R_g impact on applications
By Giuseppe Longo, Filadelfo Fusillo, Filippo Scrimizzi
Introduction
This report shows the analysis performed on Power MOSFET devices, in which the goal is
the evaluation of the intrinsic R_g parameter while it works in real applications. Generally, the
R_g parameter is an intrinsic resistance value of the device itself, which cannot be changed
because it's linked to the manufacturing process. The R_g parameter, according to the
external driving circuit, allows the switching operation mode to be defined in terms of turn-
on/off period and also coupling power dissipation of the external driver itself.
Starting from this statement, the analysis focused on devices having different intrinsic
internal R_g and these were tested in a simple testing board with a fixed driver. The various
tests performed allow us to understand the electro-thermal behavior of the device better and
to find new conclusions on this parameter, which are often not known.
November 2012
Doc ID 023815 Rev 1
1/20
www.st.com