Si4470EY_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 21.9604 N/A 5.7953 RT2 6.3818 N/A 923.7476 m RT3 13.3371 N/A 5.8236 RT4 37.9264 N/A 8.4613 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 41.6847 m N/A 54.8120 m CT2 8.8410 m N/A 1.2546 m CT3 356.1870 m N/A 12.8310 m CT4 2.0833 N/A 196.0715 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: 74305 Revision 08-May-07 www.vishay.com 1 Si4470EY_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 5.1205 N/A 1.6149 RF2 23.7400 N/A 8.9202 RF3 14.9587 N/A 7.2244 RF4 35.7281 N/A 3.2532 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 4.8970 m N/A 1.9824 m CF2 21.5550 m N/A 8.7635 m CF3 162.1276 m N/A 68.3828 m CF4 1.9274 N/A 473.3334 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: 74305 Revision 08-May-07 Si4470EY_RC Vishay Siliconix Document Number: 74305 Revision 08-May-07 www.vishay.com 3