Mathcad Estimation of Semiconductor Switch Power Losses of Voltage Regulator Modules Based on Analytical Modeling
Date Issued
2007
Date
2007
Author(s)
Hsu, Sheng-Pin
DOI
zh-TW
Abstract
Power efficiency is one of the most critical considerations in the voltage regulator modules (VRM) for computer central processor applications. These losses are becoming even more significant now as the tendency of the switching frequency is getting higher. This is the focus of thesis. Among the various loss components, it is generally true that the switching power losses associated with the various power semiconductor device are most difficult to estimate accurately.
The thesis starts with a review of several means to estimate the losses and concludes with the choice of the analytical differential equation-based model first reported by Y. Ren etc. This method is a compromise of accuracy and user friendliness. An example of a practical VRM buck converter was used to illustrate the procedures for estimating the losses and converter efficiency. The equations and the procedure were computerized in a Mathcad program for the ease of the users. Nonlinear parasitic capacitor effects of power MOSFETs, temperature effects of conduction voltage drops were taken into considerations. All the parameters of the semiconductor devices can be obtained from manufactors' datasheet. The parasitic inductances of the devices and the printed circuit board are also taken into consideration.
This program should be helpful in evaluating the power losses and the voltage rating of the power semiconductor devices.
Subjects
功率金氧半場效電晶體
電壓調節模組
解析模型
功率損耗
寄生電感
Power MOSFET
analytical model
VRM
power loss
parasitic inductance
Type
thesis