Si7458DP_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 11.5072 73.5297 m N/A RT2 1.6029 481.0169 m N/A RT3 8.8467 442.7555 m N/A RT4 43.0432 502.6979 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 713.8709 m 95.9006 u N/A CT2 6.5534 m 32.1985 m N/A CT3 55.9660 m 10.4753 m N/A CT4 1.7449 35.3560 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: 69222 Revision: 24-Jul-07 www.vishay.com 1 Si7458DP_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 5.7262 70.5542 m N/A RF2 8.7232 644.8877 m N/A RF3 19.7812 259.7859 m N/A RF4 30.7694 524.7722 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 16.1380 m 439.8910 u N/A CF2 97.4808 m 5.0258 m N/A CF3 502.8691 m 10.1882 m N/A CF4 1.7111 67.4933 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: 69222 Revision: 24-Jul-07 Si7458DP_RC Vishay Siliconix Document Number: 69222 Revision: 24-Jul-07 www.vishay.com 3