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Electronics reliability

Condensation testing of electronic assemblies

Achieving high reliability in service

As packaging densities increase and electronic assemblies move to ever-harsher environments, electrochemical reliability becomes more critical. The combination of contaminants, moisture and electrical bias facilitate electrochemical corrosion processes that result in loss of continuity or short circuits. Moisture plays an important role for circuit failures, and condensation can significantly accelerate failures.

Our systems use surface insulation resistance (SIR) measurements of the leakage currents associated with this electrochemical corrosion process. Very thin water films (~100 nm) occur naturally in high humidity environments and even other environmental changes can lead to much thicker liquid water layers, causing accelerated corrosion.  Under such conditions, insulation resistance can drop rapidly, and failures can occur within a few minutes.  Conformal coatings, or thin polymer films, are increasingly utilised to mitigate this. However, it is challenging to achieve even coverage over electronic assemblies, particularly over sharp corners. Humidity testing in combination with SIR testing provides a very effective means to characterise coating coverage. 

We have developed a proprietary platen and methodology which enables the condensation levels on test samples to be accurately and repeatably controlled, and generates representative failure modes within impressively short timescales. The condensation period and cycles can be programmed independently of the humidity conditions set in the chamber, and by depressing the temperature of the board below the ambient in the humidity chamber, controlled levels of condensation can be achieved on the test boards.  Resulting failures indicate where coating coverage is poor, allowing end-users to improve coverage or develop alternative materials or processes.

Learn more about our capabilities

Improved condensation testing to evaluate protection performance of conformal coatings
An overview of a new test method to control the rate of condensation on printed board assemblies, providing considerable improvements on existing industry standard tests. View slides

SIR, CAF and condensation testing for electronic assemblies
The advantages of using condensation testing, often in combination with SIR and CAFtesting, to evaluate assembly processes and materials. It covers vehicle design, how to conduct testing and analyse the results. Watch webinar  View slides

Find out more about our next webinar here.

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