SQ7414EN_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 4.3871 3.6273 m N/A RT2 8.3445 504.3467 m N/A RT3 11.9702 972.1139 m N/A RT4 56.2982 919.9157 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 6.4552 m 1.9260 m N/A CT2 30.8887 m 787.5516 u N/A CT3 135.2045 m 18.2079 m N/A CT4 1.2453 9.3126 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: 69756 Revision: 05-Oct-07 www.vishay.com 1 SQ7414EN_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 6.6587 6.0391 m N/A RF2 9.4845 670.9463 m N/A RF3 10.8212 1.0320 N/A RF4 54.0356 691.0146 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 5.2055 m 125.4667 u N/A CF2 19.5545 m 695.7232 u N/A CF3 119.2870 m 6.0783 m N/A CF4 1.1197 527.9622 u N/A 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: 69756 Revision: 05-Oct-07 SQ7414EN_RC Vishay Siliconix Document Number: 69756 Revision: 05-Oct-07 www.vishay.com 3