Si4431BDY_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 8.6877 N/A 2.6656 RT2 28.4684 N/A 4.1590 RT3 19.8045 N/A 14.1183 RT4 28.1071 N/A 7.0315 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 3.5586 m N/A 562.4902 µ CT2 42.5237 m N/A 79.7372 m CT3 1.6512 N/A 73.3606 m CT4 3.1236 N/A 9.0585 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: 74095 Revision 31-Aug-05 www.vishay.com 1 Si4431BDY_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 6.4712 N/A 3.1821 RF2 17.9572 N/A 10.2512 RF3 18.7986 N/A 6.9448 RF4 41.5016 N/A 7.6718 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 1.9640 m N/A 626.7851 µ CF2 19.5042 m N/A 7.0656 m CF3 85.7496 m N/A 41.7415 m CF4 1.4233 N/A 36.9009 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: 74095 Revision 31-Aug-05 Si4431BDY_RC Vishay Siliconix Document Number: 74095 Revision 31-Aug-05 www.vishay.com 3