What to Look for When Purchasing Contactors


Contactors or sockets are useful during electrical testing. This is because they make the actual contact with the DUT (device under test) so that the Automatic Test Equipment can test the device. The choice of contactor matters on all electrical tests, including a semiconductor test, as it has a significant influence on the test results. It affects the device grading, productivity of the testing, and repeatability. Picking a weak socket may lead to major faulty results due to contact issues. That effect ripples on to significant problems like indefensible machine downtimes, customer returns, or unexplained productivity issues. To prevent such issues, check for the following features;

The Socket Profile

A socket’s profile tells a lot about the contact life span and contact integrity. Modern contractors have spring-loaded pins known as pogo pins, which provide contact with the solder balls or leads of the device under testing. Such connectors offer several benefits, such as stability in the connection, ease of use, and durability. This is not the case with dated connectors. Traditional test contactors come with contacts that act like cantilevers, where the DUT’s leads can rest. The cantilevers have a spring effect in them, which allows them to oppose the force put on them by the leads. As much as they meet the functional needs, the cantilever designs have significant misgivings. Updated socket designs utilize the ‘S’ structure for the elements, which allows them to boost reliability. This is because the model focuses on the movement and attributes of the features that support the contact elements and not the actual contact elements.

Contact Elements Motion

Traditional socket designs move the contact elements directly to the leads to ensure connectivity with the DUT. However, the updated models remove the contaminants or any other unwanted items on the DUT before contact. This is known as the wiping action, which improves the efficiency and reliability of the system. Next time you are on tts, make sure you pick the most updated devices to reap the benefits.

Electrical Attributes

The electrical characteristics of the socket are very critical in determining their integrity. Factors such as the size, shape, materials, contact area of the device affect how it performs. Strive to find a socket with minimal inductive and capacitive coupling, contact resistance, stray inductance, and capacitance. These things are not as easy to identify, look carefully through product descriptions and reviews, or ask for expert guidance.

Ease of Maintenance

Maintaining a socket is not an easy task. Contactors require frequent complicated cleaning, such as laser cleaning. Thus, look for a device that you can easily clean and maintain in house. Also, consider the ease of replacing things like the contact elements, which also interfere with the test. Connectors often require replacement once their useful life is over or they are damaged. Find a socket with easily replaceable contact elements.

Sockets provide the best solutions for tests where replacements are more economical. Before you get any contactor, ensure you understand fully how it works as you will do most of the cleaning and replacing. This way, you can get the best results at the lowest cost.