7.4 Thermal Information
THERMAL METRIC(1) |
UCC27533, UCC27536, UCC27537 |
UCC27531, UCC27538 |
UCC27531 |
UNIT |
DBV |
DBV |
SOIC |
5 PINS |
6 PINS |
8 PINS |
RθJA |
Junction-to-ambient thermal resistance(2) |
178.3 |
178.3 |
129.9 |
°C/W |
RθJC(top) |
Junction-to-case (top) thermal resistance(3) |
109.7 |
109.7 |
79.9 |
RθJB |
Junction-to-board thermal resistance(4) |
28.3 |
28.3 |
68.1 |
ψJT |
Junction-to-top characterization parameter(5) |
14.7 |
14.7 |
22.7 |
ψJB |
Junction-to-board characterization parameter(6) |
27.8 |
27.8 |
69.8 |
(1) For more information about traditional and new thermal metrics, see the
Semiconductor and IC Package Thermal Metrics application report (
SPRA953).
(2) The junction-to-ambient thermal resistance under natural convection is obtained in a simulation on a JEDEC-standard, high-K board, as specified in JESD51-7, in an environment described in JESD51-2a.
(3) The junction-to-case (top) thermal resistance is obtained by simulating a cold plate test on the package top. No specific JEDEC-standard test exists, but a close description can be found in the ANSI SEMI standard G30-88.
(4) The junction-to-board thermal resistance is obtained by simulating in an environment with a ring cold plate fixture to control the PCB temperature, as described in JESD51-8.
(5) The junction-to-top characterization parameter, ψJT, estimates the junction temperature of a device in a real system and is extracted from the simulation data for obtaining RθJA, using a procedure described in JESD51-2a (sections 6 and 7).
(6) The junction-to-board characterization parameter, ψJB, estimates the junction temperature of a device in a real system and is extracted from the simulation data for obtaining RθJA, using a procedure described in JESD51-2a (sections 6 and 7).