Si8429DB_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) Junction to Ambient Case Foot RT1 11.1229 N/A 1.1121 RT2 18.8666 N/A 4.7779 RT3 45.8097 N/A 1.1097 RT4 9.2008 N/A 13.0003 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 1.2796 m N/A 655.6456 u CT2 3.9286 m N/A 5.8821 m CT3 1.3734 N/A 262.0076 m CT4 182.5361 m N/A 2.0022 m 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: 69752 Revision: 05-Oct-07 www.vishay.com 1 Si8429DB_RC Vishay Siliconix R-C THERMAL MODEL FOR FILTER CONFIGURATION R-C VALUES FOR FILTER CONFIGURATION Thermal Resistance (°C/W) Junction to Ambient Case Foot RF1 14.3727 N/A 4.0537 RF2 15.8853 N/A 14.8545 RF3 10.7666 N/A 787.3600 m RF4 43.9754 N/A 304.4400 m Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 871.6762 u N/A 656.2894 u CF2 2.5486 m N/A 1.0594 m CF3 135.4187 m N/A 246.2120 m CF4 1.2704 N/A 2.3664 m 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: 69752 Revision: 05-Oct-07 Si8429DB_RC Vishay Siliconix Document Number: 69752 Revision: 05-Oct-07 www.vishay.com 3