Residual material detection in backdrilled stubs
US9488690B2 · kind B2 · utility
4Cited by
7References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2014 |
| Grant date | Nov 8, 2016 |
| Priority date | — |
| Expiry date | Apr 1, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T408/05
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A stub of a via formed in a printed circuit board is backdrilled to a predetermined depth. A capacitance probe is positioned within the via. Then the capacitance probe is used to obtain a test capacitance measurement. The test capacitance measurement is compared to a predetermined baseline capacitance measurement. Residual conductive plating material in the backdrilled stub causes the test capacitance measurement to exceed the predetermined baseline capacitance measurement. An indication is made that the predetermined baseline capacitance measurement has been exceeded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.