Si5481DU_RC Vishay Siliconix R-C Thermal Model Parameters DESCRIPTION The parametric values in the R-C thermal model have been derived using curve-fitting techniques. These techniques are described in "A Simple Method of Generating Thermal Models for a Power MOSFET"[1]. When implemented in P-Spice, these values have matching characteristic curves to the Single Pulse Transient Thermal Impedance curves for the MOSFET. R-C values for the electrical circuit in the Foster/Tank and Cauer/Filter configurations are included. Note: For a detailed explanation of implementing these values in P-SPICE, refer to Application Note AN609 Thermal Simulations Of Power MOSFETs on P-SPICE Platform. R-C THERMAL MODEL FOR TANK CONFIGURATION R-C VALUES FOR TANK CONFIGURATION Thermal Resistance (°C/W) Foot Junction to Ambient Case RT1 7.5207 26.3743 m N/A RT2 11.0638 203.9247 m N/A RT3 12.6090 1.8408 N/A RT4 58.7691 4.9380 N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 769.1519 u 238.1683 u N/A CT2 214.0259 m 3.6083 m N/A CT3 11.5381 m 283.8532 u N/A CT4 1.3933 1.7721 m N/A This document is intended as a SPICE modeling guideline and does not constitute a commercial product data sheet. Designers should refer to the appropriate data sheet of the same number for guaranteed specification limits. Document Number: 74270 Revision: 20-Jun-07 www.vishay.com 1 Si5481DU_RC Vishay Siliconix R-C THERMAL MODEL FOR FILTER CONFIGURATION R-C VALUES FOR FILTER CONFIGURATION Thermal Resistance (°C/W) Foot Junction to Ambient Case RF1 10.0999 592.2451 m N/A RF2 12.5786 2.1879 N/A RF3 11.8471 152.2398 m N/A RF4 55.3578 4.0525 N/A Junction to Ambient Case Foot CF1 881.6825 u 103.2942 u N/A CF2 14.7663 m 207.3824 u N/A CF3 211.8552 m 1.6241 m N/A CF4 1.2197 168.4468 u N/A Thermal Capacitance (Joules/°C) Note: NA indicates not applicable Reference: [1] "A Simple Method of Generating Thermal Models for a Power MOSFET" by Wharton McDaniel and Kandarp Pandya, IEEE / SEMITHERM 2002 www.vishay.com 2 Document Number: 74270 Revision: 20-Jun-07 Si5481DU_RC Vishay Siliconix Document Number: 74270 Revision: 20-Jun-07 www.vishay.com 3