Multilayer type printed-wiring board and method of measuring impedance of multilayer type printed-wiring board
US6512181B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2001 |
| Grant date | Jan 28, 2003 |
| Priority date | — |
| Expiry date | Feb 28, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R31/2822
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The impedance of a newly manufactured data transmission wire pattern can be measured easily and accurately. A multilayer type printed-wiring board 1 comprises a pair of data transmission wire patterns 4, 5 arranged between a CPU module 2 and a memory module 3 on respective inner layer substrates 6, 7, impedance measuring wire patterns 21 and 22 arranged respectively in the layers same as those of the data transmission wire patterns 4, 5, a prepreg layer 11 arranged on the impedance measuring wire patterns 21, 22, land sections 23, 23 for signals arranged on the prepreg layer 11 and electrically connected to the impedance measuring wire patterns 21, 22 so as to be brought into contact with the signal terminal 41 of a probe 40 and a GND land section 24 also arranged on the prepreg layer 11 and electrically connected to the impedance measuring wire patterns 21, 22 so as to be brought into contact with the GND terminal 42 of the probe 40, the impedance measuring wire patterns 21, 22 having a pattern length not smaller than 30 mm that is the minimal length required for use with a TDR unit and a pattern width same as that of the data transmission wire patterns 4, 5.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.