CODA-PIN Contact Probes & Interfacing Components

What are Test Probes?

Test probes - test pins - spring probes - pogo pins; these are all generic terms to describe a component whose spring loaded tip will provide a reliable electrical contact to a target where the distance away may well be variable. They have been used for many years to make simultaneous contact to a number of test points on printed circuit boards to test functionality and for measuring component values. They are especially used in test fixtures associated with automatic test equipment (ATE).

Another application is for the functional testing of components, sub-assemblies and finished cable harnesses where the probes may be used inside the functional test station, as part of a production line.

The test probe uses a metal tube, ready assembled with the spring and the plunger as a one-piece item. Probes are generally gold plated because gold is an excellent conductor of electricity.

Each type of probe can be supplied with a variety of plunger tip styles and spring pressures, enabling the most suitable probe to be selected, to make the most reliable contact onto the target. Some tipstyles are sharp with single or multiple daggers to enable the tip to penetrate dirt or solder flux. Others are rounded or blunt to avoid damage to the target/unit under test. We also supply several series of test probes which have extremely sharp tipstyles for use in lead free environments where flux build up can be a problem.

Most series of probes are mounted into a receptacle. This is a metal sleeve into which the probe slides into. The electrical connection is then made to the receptacle and not the probe. This allows the probe to be easily removed for cleaning or replacement.

The illustration shows a test probe and its receptacle mounted in a block with the electrical connection made to the tail of the receptacle. A variety of receptacles are available allowing several different methods of making the electrical connection.