Si4804BDY_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 17.7264 N/A 15.7415 RT2 2.6324 N/A 2.2019 RT3 34.7338 N/A 15.5514 RT4 54.4627 N/A 6.8595 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 4.9531 m N/A 4.7655 m CT2 8.9425 m N/A 426.8169 u CT3 45.8398 m N/A 105.9687 m CT4 1.0431 N/A 89.5748 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: 70365 Revision 19-Mar-07 www.vishay.com 1 Si4804BDY_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 9.9712 N/A 2.8820 RF2 21.3197 N/A 18.2884 RF3 29.0574 N/A 8.7076 RF4 49.2614 N/A 10.4393 Junction to Ambient Case Foot CF1 2.2098 m N/A 476.9172 u CF2 6.5082 m N/A 4.1262 m CF3 61.9906 m N/A 43.2595 m CF4 1.0971 N/A 69.3897 m Thermal Capacitance (Joules/°C) 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: 70365 Revision 19-Mar-07 Si4804BDY_RC Vishay Siliconix Document Number: 70365 Revision 19-Mar-07 www.vishay.com 3