Wiring board for testing loaded printed circuit board

• US 9,753,058 B2
• Filed: 10/30/2014
• Issued: 09/05/2017
• Est. Priority Date: 12/17/2009
• Status: Active Grant

• Current Assignee: Xcerra Corporation (COHU Incorporated)
• Original Assignee: Xcerra Corporation (COHU Incorporated)
• Inventors: Swart, Mark A., Snyder, Kenneth R., Koolis, Stephen J., Tackett, Douglas W.
• Primary Examiner(s): Astacio-Oquendo, Giovanni
• Application Number:
  US14/529,033
• Publication Number:
  US 20150054539A1
• Time in Patent Office: 1,041 Days
• Field of Search: 32475407, 32475605, 324754, 324755, 324758, 324761
• CPC Class Codes: G01R 1/07378 using an intermediate adapter, e.g. space transformers G01R1/07371 takes precedence
• CPC Class Codes: G01R 31/2801 Testing of printed circuits, backplanes, motherboards, hybrid circuits or carriers for multichip packages [MCP] G01R31/318508 takes precedence; contactless testing G01R31/302; testing contacts or connections G01R31/66
• CPC Class Codes: G01R 31/2844 using test interfaces, e.g. adapters, test boxes, switches, PIN drivers G01R31/2889 takes precedence
• CPC Class Codes: G01R 31/31905 Interface with the device under test [DUT], e.g. arrangements between the test head and the DUT, mechanical aspects, fixture
• CPC Class Codes: Y10T 29/49126 Assembling bases

Abstract

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.

Claims

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.