Browse Prior Art Database

COST EFFECTIVE HEATSINKING FOR SMT ELECTRONICS

IP.com Disclosure Number: IPCOM000009010D
Original Publication Date: 1999-Jan-01
Included in the Prior Art Database: 2002-Jul-31
Document File: 2 page(s) / 77K

Publishing Venue

Motorola

Related People

Roger Humphreys: AUTHOR [+3]

Abstract

Heatsinking has always been one of the main challenges in the mechanical design of electrical systems such as engine management modules. A cost-effective solution to dissipate the heat of SMT components on FR4 substrate had to be developed considering the following requirements: wide) were used, but different features were devel- oped to optimize the quality of the contact: the bottom metal part can be curved to limit the effect of the bending 'due to screwing and allow a good pressure even in the middle part of the con- tact area.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 54% of the total text.

Page 1 of 2

0 M

MOTOROLA Technical Developments

COST EFFECTIVE HEATSINKING~

FOR SMT ELECTRONICS

by Roger Humphreys, Andrew McCulloch and Fabien Malacarne

BACKGROUND

  Heatsinking has always been one of the main challenges in the mechanical design of electrical systems such as engine management modules. A cost-effective solution to dissipate the heat of SMT components on FR4 substrate had to be developed considering the following requirements:

wide) were used, but different features were devel- oped to optimize the quality of the contact:

   the bottom metal part can be curved to limit the effect of the bending 'due to screwing and allow a good pressure even in the middle part of the con- tact area.

l

l

l PCB must allow double sided placement.

l

   PCB cost must be low. Then, the use of processed PCB - like thin FR4 bonded on rigidiser or local heatsinks bonded on FR4 (PowerFR4 approach) - must be avoided.

   slightly local raised ,areas can be created on the bottom metal part at the power components pad location. That metal part can be made of stamped sheet metal for low cost; a half shear process can be performed to get typically 0.2mm high local raised areas.

This configuration was thermally tested and showed a good thermal dissipation capability.

The result is a low cost mechanics typically consisting:

l the assembly must be simple.

SOLUTION

The following original solution was designed:

  The PCB is a two-sided board with all its power components located along its two sides (at 90" to...