Si5943DU_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 26.9457 4.0321 N/A RT2 6.7302 4.4398 N/A RT3 20.4524 1.7651 N/A RT4 50.4071 4.8035 N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 4.3260 m 184.9208 u N/A CT2 280.1667 u 4.8811 m N/A CT3 77.3715 m 16.1497 m N/A CT4 1.5542 2.7666 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: 74271 Revision: 27-Jun-07 www.vishay.com 1 Si5943DU_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 6.7602 5.4496 N/A RF2 28.3247 9.2239 N/A RF3 20.6980 164.6409 m N/A RF4 48.7669 290.6457 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 220.9423 u 161.3129 u N/A CF2 3.4499 m 1.8277 m N/A CF3 63.0446 m 185.9015 m N/A CF4 1.5334 6.0479 u 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: 74271 Revision: 27-Jun-07 Si5943DU_RC Vishay Siliconix Document Number: 74271 Revision: 27-Jun-07 www.vishay.com 3