When manufacturing high volumes of discrete components, circuit devices or electronic equipment it is often desirous to utilize a test fixture. The test fixture is used to hold the device while rapidly performing any number of tests to determine its proper operation. In the event the test fixture determines some malfunction, the device can then be discarded or removed for repair.
The test fixture structure may take on many overall forms but often includes a number of test pins which mate with corresponding pads or pins on the device under test. To enable the test fixture to operate properly and give correct test data, it is imperative that each of the pins on the test fixture and device's test area mate properly to form a good electrical connection. Even though a variety of pin types are utilized in the industry, these most often only provide about a 98% reliability. This figure however is inadequate when dealing with high manufacturing volumes. Too many devices would be tested with an improper connection giving erroneous data, high scrap and retest costs.
One problem associated with this type of test structure is many of the devices which are under test include rosin, rubber, plastic, organic or other protective material which cover the device's test contact points. These materials are flux residue's from the soldering process or are intended to shield the device to prevent aging. Problems arise when the device is inserted into the test fixture and these coating materials prevent or inhibit a good electrical connect. In turn, the test fixture then gives faulty indications and test data. This ultimately leads to the device being discarded, retested or repaired when in fact it had no defects. Thus, one of the faults associated with the test fixture is that it does not consistently make adequate electrical contact between test fixture and test device. This causes a high reject rate and product expense only to determine the device is operational.
Therefore, it was realized that the need exists to provide a means to insure highly reliable contact between the test fixture and the device test area without being difficult or cumbersome to use. The test device should be capable of easy installation into the test fixture without added interference to other contact's or test pins.