Effect of a current-sensing resistor on required MOSFET size

Author

Bryant, Brad ; Kazimierczuk, Marian K.

Author_Institution

Dept. of Electr. Eng., Wright State Univ., Dayton, OH, USA

Volume

50

Issue

5

fYear

2003

fDate

5/1/2003 12:00:00 AM

Firstpage

708

Lastpage

711

Abstract

The effect of a current-sensing resistor used in current-mode control of pulsewidth modulator (PWM) converters on required MOSFET aspect ratio, the ratio of channel width to channel length generally known as W/L, is studied. The results can also be applied to the effect of source parasitic resistance in a power MOSFET. These resistances require a significant increase in aspect ratio to achieve a desired maximum current capability. Experimental results are presented verifying the validity of the theoretical results.

Keywords

DC-DC power convertors; MOSFET circuits; PWM power convertors; current-mode circuits; power MOSFET; resistors; semiconductor device models; MOSFET aspect ratio; PWM dc/dc power converters; channel width to channel length ratio; current-mode control; current-sensing resistor; maximum current capability; power MOSFET model; pulsewidth modulator converters; source parasitic resistance; Electric resistance; MOSFET circuits; Power MOSFET; Pulse width modulation; Pulse width modulation converters; Resistors; Size control; Switches; Switching converters; Threshold voltage;

fLanguage

English

Journal_Title

Circuits and Systems I: Fundamental Theory and Applications, IEEE Transactions on

Publisher

ieee

ISSN

1057-7122

Type

jour

DOI

10.1109/TCSI.2003.811024

Filename

1203834