Si4835BDY_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 5.0948 N/A 2.9711 RT2 25.6090 N/A 947.4000 m RT3 5.1187 N/A 12.2133 RT4 49.1775 N/A 5.8682 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 4.4326 m N/A 18.0077 m CT2 56.9940 m N/A 1.4113 m CT3 69.4006 m N/A 105.1767 m CT4 1.1078 N/A 18.1107 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: 74625 Revision: 14-May-07 www.vishay.com 1 Si4835BDY_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 7.4107 N/A 1.9199 RF2 28.2886 N/A 9.5259 RF3 15.5024 N/A 8.5941 RF4 33.7983 N/A 1.9601 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 4.4021 m N/A 1.6616 m CF2 34.2059 m N/A 8.4846 m CF3 687.5230 m N/A 109.4043 m CF4 694.4768 m N/A 4.0316 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: 74625 Revision: 14-May-07 Si4835BDY_RC Vishay Siliconix Document Number: 74625 Revision: 14-May-07 www.vishay.com 3