SiA811DJ_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 Mosfet Ambient Schottky Foot Case Mosfet Case Schottky RT1 12.1637 14.9494 N/A 5.7765 6.5467 RT2 25.6565 19.0021 N/A 3.7748 4.3575 RT3 27.9663 20.0917 N/A 2.3175 2.8124 RT4 44.2135 55.9568 N/A 4.1312 4.7834 Thermal Capacitance (Joules/°C) Junction to Ambient Mosfet Ambient Schottky Foot Case Mosfet Case Schottky CT1 90.4249 u 44.2860 u N/A 534.8325 u 389.0875 u CT2 1.8178 m 1.4025 m N/A 89.9295 u 49.6774 u CT3 26.7261 m 33.9500 m N/A 148.7090 u 51.6465 u CT4 1.0568 1.4683 N/A 411.8908 u 227.5644 u 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: 69293 Revision: 10-Aug-07 www.vishay.com 1 SiA811DJ_RC Vishay Siliconix R-C THERMAL MODEL FOR FILTER CONFIGURATION R-C VALUES FOR FILTER CONFIGURATION Thermal Resistance (°C/W) Junction to Ambient Mosfet Ambient Schottky Foot Case Mosfet Case Schottky RF1 16.6834 15.8821 N/A 8.7745 9.2052 RF2 31.9645 21.5723 N/A 3.8432 5.5541 RF3 21.7849 16.8410 N/A 1.7466 2.1892 RF4 39.5672 55.7046 N/A 1.6357 1.5515 Case Mosfet Case Schottky 23.0729 u Thermal Capacitance (Joules/°C) Junction to Ambient Mosfet Ambient Schottky Foot CF1 112.9584 u 42.3510 u N/A 45.4623 u CF2 2.6995 m 1.4711 m N/A 196.9465 u 93.1985 u CF3 63.9442 m 42.0397 m N/A 383.0379 u 538.7457 u CF4 1.2074 1.3816 N/A 98.0442 u 942.4790 u 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: 69293 Revision: 10-Aug-07 SiA811DJ_RC Vishay Siliconix Document Number: 69293 Revision: 10-Aug-07 www.vishay.com 3 SiA811DJ_RC Vishay Siliconix www.vishay.com 4 Document Number: 69293 Revision: 10-Aug-07