Si4484EY_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 4.9280 N/A 536.3249 m RT2 26.4288 N/A 4.6553 RT3 26.4135 N/A 10.1038 RT4 27.3492 N/A 5.6867 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 7.0702 m N/A 644.2123 µ CT2 45.4725 m N/A 65.5331 m CT3 1.8744 N/A 157.8483 m CT4 4.2541 N/A 10.8807 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: 74107 Revision 02-Sep-05 www.vishay.com 1 Si4484EY_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 2.6273 N/A 2.7852 RF2 27.5087 N/A 8.1195 RF3 23.0822 N/A 5.8581 RF4 31.8094 N/A 4.2091 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 1.0532 m N/A 3.5316 m CF2 30.2590 m N/A 10.7913 m CF3 783.3855 m N/A 104.4945 m CF4 1.7732 N/A 59.3930 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: 74107 Revision 02-Sep-05 Si4484EY_RC Vishay Siliconix Document Number: 74107 Revision 02-Sep-05 www.vishay.com 3