Si4447DY_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 8.1551 N/A 19.0682 RT2 29.8274 N/A 3.4197 RT3 14.4661 N/A 14.5204 RT4 57.5514 N/A 2.9917 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 1.1056 m N/A 67.9737 m 360.9499 u CT2 18.9141 m N/A CT3 146.2789 m N/A 6.4281 m CT4 1.3108 N/A 10.3350 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: 74816 Revision: 19-Jul-07 www.vishay.com 1 Si4447DY_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 9.2561 N/A 5.2763 RF2 19.2431 N/A 16.3258 RF3 24.8792 N/A 4.4271 RF4 56.6216 N/A 13.9708 Junction to Ambient Thermal Capacitance (Joules/°C) Case Foot 419.8312 u CF1 1.0868 m N/A CF2 12.7918 m N/A 4.4691 m CF3 21.1836 m N/A 21.2194 m CF4 1.2680 N/A 68.9719 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: 74816 Revision: 19-Jul-07 Si4447DY_RC Vishay Siliconix Document Number: 74816 Revision: 19-Jul-07 www.vishay.com 3