Si4864DY_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 18.3700 N/A 5.0412 RT2 6.5597 N/A 4.6217 RT3 18.0816 N/A 482.9088 m RT4 35.6388 N/A 5.8220 Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 86.3027 m N/A 17.9107 m CT2 23.0335 m N/A 163.2064 m CT3 2.1550 N/A 4.9535 m CT4 3.0729 N/A 352.6703 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: 70368 Revision 19-Mar-07 www.vishay.com 1 Si4864DY_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 6.0264 N/A 1.8131 RF2 19.1477 N/A 6.2051 RF3 21.3201 N/A 7.0589 RF4 32.3275 N/A 899.3765 m Junction to Ambient Case CF1 13.0130 m N/A 7.1559 m CF2 46.5802 m N/A 12.6441 m CF3 856.5592 m N/A 154.0294 m CF4 1.7078 N/A 2.2187 Thermal Capacitance (Joules/°C) Foot 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: 70368 Revision 19-Mar-07 Si4864DY_RC Vishay Siliconix Document Number: 70368 Revision 19-Mar-07 www.vishay.com 3