Si7804DN_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 2.2354 1.4398 N/A RT2 11.4663 1.3399 N/A RT3 11.4042 132.8000 m N/A RT4 55.8941 3.0875 N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CT1 2.5926 m 8.5782 m N/A CT2 178.7170 m 353.1913 u N/A CT3 17.5835 m 1.2742 N/A CT4 1.2765 4.1972 m N/A 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: 69246 Revision: 27-Jul-07 www.vishay.com 1 Si7804DN_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 4.6780 1.8322 N/A RF2 14.0198 2.0587 N/A RF3 13.1404 1.6657 N/A RF4 49.1618 443.4000 m N/A Thermal Capacitance (Joules/°C) Junction to Ambient Case Foot CF1 4.0938 m 349.0011 u N/A CF2 17.5857 m 2.4590 m N/A CF3 301.6096 m 1.3150 m N/A CF4 1.1309 48.0961 m N/A 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: 69246 Revision: 27-Jul-07 Si7804DN_RC Vishay Siliconix Document Number: 69246 Revision: 27-Jul-07 www.vishay.com 3