Si4874BDY_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 31.0829 N/A 531.9000 m RT2 3.4656 N/A 4.0685 RT3 20.2205 N/A 8.3295 RT4 25.2310 N/A 8.0701 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 387.0355 m N/A 1.7792 m CT2 6.6225 m N/A 13.2059 m CT3 30.6901 m N/A 173.7542 m CT4 4.5429 N/A 18.2511 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: 69234 Revision: 26-Jul-07 www.vishay.com 1 Si4874BDY_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 11.4701 N/A 1.1453 RF2 19.1685 N/A 10.9244 RF3 30.3075 N/A 5.2964 RF4 19.0539 N/A 3.6339 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 9.4371 m N/A 2.5171 m CF2 44.9154 m N/A 5.3154 m CF3 405.1807 m N/A 73.8924 m CF4 5.7272 N/A 365.1368 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: 69234 Revision: 26-Jul-07 Si4874BDY_RC Vishay Siliconix Document Number: 69234 Revision: 26-Jul-07 www.vishay.com 3