Si5938DU_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 Ch1 Ambient Ch2 Foot Case Ch1 Case Ch2 RT1 29.1249 29.1249 N/A 12.4930 u 12.4930 u RT2 6.9670 6.9670 N/A 7.8166 7.8166 RT3 18.5813 18.5813 N/A 3.8770 3.8770 RT4 50.1264 50.1264 N/A 3.3831 3.3831 Thermal Capacitance (Joules/°C) Junction to Ambient Ch1 Ambient Ch2 Foot Case Ch1 Case Ch2 CT1 4.5843 m 4.5843 m N/A 3.3132 u 3.3132 u CT2 283.6337 u 283.6339 u N/A 2.6715 m 2.6715 m CT3 107.8785 m 107.8774 m N/A 164.1373 u 164.1373 u CT4 1.5756 1.5756 N/A 3.3150 m 3.3150 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: 74266 Revision: 27-Jun-07 www.vishay.com 1 Si5938DU_RC Vishay Siliconix R-C THERMAL MODEL FOR FILTER CONFIGURATION R-C VALUES FOR FILTER CONFIGURATION Thermal Resistance (°C/W) Junction to Ambient Ch1 Ambient Ch2 Foot Case Ch1 RF1 9.3413 9.3413 N/A 5.5864 Case Ch2 5.5864 RF2 29.9229 29.9229 N/A 2.3591 2.3591 RF3 18.5687 18.5687 N/A 6.5605 6.5605 RF4 47.0389 47.0389 N/A 511.4712 m 511.4712 m Junction to Ambient Ch1 Ambient Ch2 Foot Case Ch1 Case Ch2 CF1 356.4665 u 356.4659 u N/A 174.6616 u 174.6616 u CF2 4.6000 m 4.6000 m N/A 1.8003 m 1.8003 m CF3 116.2235 m 116.2234 m N/A 183.9506 u 183.9506 u CF4 1.5853 1.5853 N/A 5.4784 m 5.4784 m Thermal Capacitance (Joules/°C) 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: 74266 Revision: 27-Jun-07 Si5938DU_RC Vishay Siliconix Document Number: 74266 Revision: 27-Jun-07 www.vishay.com 3 Si5938DU_RC Vishay Siliconix www.vishay.com 4 Document Number: 74266 Revision: 27-Jun-07