Fine pitch test probes
Using fine pitch probes, very small test points can be contacted in a small grid. In some cases, these are installed without a receptacle. Fine pitch test probes are used for test points positioned close together, which cannot be contacted by standard test probes. INGUN defines fine pitch contacting as contacting in grids smaller than 1.27 mm/50 Mil.
Test probes used with receptacles are changed from top side in the usual way, without breaking the electrical connection. In order to avoid elaborate wiring of the receptacle, use of pre-wired receptacles is preferred. Test probes with a plug connection can be used without a receptacle to enable them to also be used for small grids. The plug is usually pressed or glued into the plug mounting plate. The probes have a floating mount in the probe plate and are centred and secured by means of a holding guide plate. This type of customising has the following advantages:
- Contacting of very small pads (can be used in grids smaller that probes with receptacles)
- High contacting accuracy due to low ‘wobble’ of the test probe in the holding guide plate
- Sandwich assembly of test fixture possible
- Larger drilling tolerances permitted in the probe plate