In my previous column, I highlighted a few cautionary notes on the pain points associated with thermal management products, particularly the choices that you will be confronted with, such as which material or product type (i.e., pad or paste) is best suited to your application. In this column, I will underline the importance of getting it right, and touch on the consequences if you don’t.
There are a variety of materials and methods to choose from, and they serve different purposes depending upon the physical constraints of the application, component layout and assembly geometry, the environment in which the assembly will be placed, the severity of duty, etc. Then, there are some more specific questions to ask, such as: what thermal conductivity do I require, or how much material will be needed in the interface between component and heat sink to achieve a thermally stable assembly?
Overlook the slightest detail, and you could compromise the performance of your electronic assembly. Clearly, poor thermal management practice will affect the efficiency of dissipating heat away from components and safely out of the assembly. As the temperature of a component increases and reaches its equilibrium temperature, the rate of heat loss per second will equate to the heat produced per second within the component. This temperature may be high enough to significantly shorten the life of the component or even cause the device to fail unless adequate thermal management measures are taken.
Of course, the same applies to a complete circuit or device, which has individual heat producing components within it. In this case, inadequately thermally managed components will almost certainly overheat, which will negatively impact the surrounding components and lead to reduced life expectancy for those components or even their complete failure in service.
Poor reliability arising from thermally induced circuit failures might prove detrimental to brand reputation, but what if the application served a critical role? Applications might include the following:
- A safety-critical device upon which the safety of personnel working in a hazardous environment might depend
- A device that simply would not function without proper thermal management procedures in place
- A device with a defined working temperature range when in use
- A piece of equipment designed to work in harsh or extreme conditions, which must work reliably regardless of those conditions
To read this entire column, which appeared in the May 2019 issue of Design007 Magazine, click here.