Si5904DC_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 28.8997 N/A 22.9528 RT2 7.3047 N/A 5.9111 RT3 20.9223 N/A 1.7928 RT4 52.5607 N/A 9.9214 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 1.4667 m N/A 980.9062 u CT2 165.3221 u N/A 168.5356 u CT3 32.4158 m N/A 2.5381 CT4 1.3579 N/A 13.6418 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: 74023 Revision: 27-Jun-07 www.vishay.com 1 Si5904DC_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 9.9324 N/A 5.3124 RF2 28.9353 N/A 16.3119 RF3 19.4955 N/A 14.0691 RF4 51.4401 N/A 4.0773 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 170.1651 u N/A 105.4782 u CF2 1.3594 m N/A 549.2108 u CF3 32.6863 m N/A 1.7158 m CF4 1.3801 N/A 70.8657 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: 74023 Revision: 27-Jun-07 Si5904DC_RC Vishay Siliconix Document Number: 74023 Revision: 27-Jun-07 www.vishay.com 3