Si5947DU_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 23.9495 3.2047 N/A RT2 7.4394 3.6406 N/A RT3 20.5850 840.6781 m N/A RT4 51.8046 4.3986 N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 2.7487 m 203.1695 u N/A CT2 153.7000 u 3.0822 m N/A CT3 48.1399 m 94.0577 m N/A CT4 859.7477 m 4.5020 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: 74273 Revision: 27-Jun-07 www.vishay.com 1 Si5947DU_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 7.2873 3.7301 N/A RF2 25.4282 7.7159 N/A RF3 21.3216 312.3665 m N/A RF4 49.7799 280.0256 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 114.2154 u 172.9052 u N/A CF2 2.1753 m 1.8086 m N/A CF3 41.1592 m 209.1828 m N/A CF4 841.2034 m 5.2915 m 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: 74273 Revision: 27-Jun-07 Si5947DU_RC Vishay Siliconix Document Number: 74273 Revision: 27-Jun-07 www.vishay.com 3