Si4838DY_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 7.0758 N/A 7.5020 RT2 17.0370 N/A 897.3355 m RT3 17.4688 N/A 4.7711 RT4 38.1489 N/A 2.8545 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 19.3780 m N/A 133.8260 m CT2 2.0410 N/A 66.9080 m CT3 87.3563 m N/A 16.5866 m CT4 2.9754 N/A 1.6241 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: 70366 Revision 19-Mar-07 www.vishay.com 1 Si4838DY_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 7.3547 N/A 979.6962 m RF2 18.0073 N/A 5.5894 RF3 17.9905 N/A 4.3890 RF4 35.8741 N/A 4.9596 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 14.1504 m N/A 6.9088 m CF2 48.5475 m N/A 7.2628 m CF3 824.9106 m N/A 81.9651 m CF4 1.4196 N/A 260.4108 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: 70366 Revision 19-Mar-07 Si4838DY_RC Vishay Siliconix Document Number: 70366 Revision 19-Mar-07 www.vishay.com 3