Wiring board for testing loaded printed circuit board
View Patent ↗A wiring board for transmission of test signals between test point locations on a circuit board under test and an external analyzer having compliant contacts making electrical contact with a pad positioned on a conductive surface circuit layer having a trace extending to a second pad having a hole for receipt of an interface pin having a swaged head electrically connected to the external analyzer.
1. A wiring board for transmission of test signals between test point locations on a circuit board under test and an external test analyzer comprising:
a single non-conductive board having a conductive circuit layer positioned on a top surface, the conductive circuit layer having a conductive first pad without a hole in the single non-conductive board and a conductive trace extending to a conductive second pad positioned around a hole extending through the single non-conductive board for receipt of an interface pin extending through the single non-conductive board; and
a compliant contact making electrical contact with the test point locations and the conductive first pad of the circuit layer.
2. The wiring board of claim 1 , wherein there are multiple conductive circuits layered on top of one another on the single non-conductive board.
3. The wiring board of claim 2 , wherein there is a compliant contact and an interface pin for each conductive circuit.
4. The wiring board of claim 1 , wherein the conductive second pad is a via.
5. The wiring board of claim 4 , wherein the interface pin extends through the via.
6. The wiring board of claim 4 , wherein a short headless pin extends through the via for the sole purpose of connecting the conductive second pad on one layer to another layer.
7. The wiring board of claim 4 , wherein the via has at least one flap around an opening which engages the interface pin.
8. The wiring board of claim 6 , wherein vias on successive layers have at least one flap rotated with respect to adjacent layers.
9. The wiring board of claim 1 , wherein the interface pin has a smooth round portion for contacting the conductive second pad at the middle or end of a trace.
10. The wiring board of claim 1 , wherein the conductive second pad is a via.
11. The wiring board of claim 1 , wherein the interface pin has a swaged or crimped feature for mechanical retention.
12. The wiring board of claim 1 , wherein the interface pin is piano or music wire.
13. The wiring board of claim 1 , further having a spare interface pin extending from a bottom of the wiring board which is wired to a rework receptacle.
14. The wiring board of claim 1 , further having a replacement interface pin extending from a bottom of the wiring board which is wired to a short pin when an offset of the interface pin is too large to tilt or bend into a normal position.
15. The wiring board of claim 1 , further comprising a probe socket extending through the non-conductive board for repair purposes or for the support of special purpose test probes.
16. The wiring board of claim 1 , wherein height of the test probes are controlled by a depth of a counter bore in a top plate so that the height is set for optimal compression when testing solder mask defined (SMD) lands or component leads of varying heights.