Si4825DY_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 configuration are included. The corresponding values for the Cauer/Filter configuration are available upon request. 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 2.7427 N/A 295.2058 m RT2 28.2942 N/A 4.9892 RT3 30.2729 N/A 7.3456 RT4 23.9546 N/A 5.2956 Junction to Ambient Case Foot CT1 11.6164 m N/A 19.8634 m CT2 40.4911 m N/A 136.8264 m CT3 1.9161 N/A 200.8471 m CT4 4.8112 N/A 9.7046 m Thermal Capacitance (Joules/°C) 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:74112 Revision 14-Nov-05 www.vishay.com 1 Si4825DY_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 3.8763 N/A 3.2479 RF2 28.2881 N/A 4.6112 RF3 27.2423 N/A 6.3565 RF4 25.8659 N/V 3.6323 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 6.9709 m N/A 5.6845 m CF2 30.8175 m N/A 10.3060 m CF3 1.1588 N/A 94.6268 m CF4 1.2584 N/A 25.0449 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:74112 Revision 14-Nov-05 Si4825DY_RC Vishay Siliconix Document Number:74112 Revision 14-Nov-05 www.vishay.com 3