Method and probe structure for implementing a single probe location for multiple signals

• US 20050077912A1
• Filed: 10/09/2003
• Published: 04/14/2005
• Est. Priority Date: 10/09/2003
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bartley, Gerald Keith, Germann, Philip Raymond, Dahlen, Paul Eric, Maxson, Mark Owen, Maki, Andrew B.
• Granted Patent: US 6,987,397 B2
• Time in Patent Office: Days
• US Class Current: 324/754.30
• CPC Class Codes: G01R 1/07328 for testing printed circuit boards
• CPC Class Codes: G01R 31/2808 Holding, conveying or contacting devices, e.g. test adapters, edge connectors, extender boards probe, multiprobe, probe manipulator or probe fixture G01R1/067
• CPC Class Codes: H05K 3/222 Completing of printed circuits by adding non-printed jumper connections printed jumper connections H05K3/4685

Abstract

A method and a probe structure are provided for implementing multiple signals probing of a printed circuit board. A probe structure is formed on an outside surface of the printed circuit board. A resistor is electrically connected with an associated via with a signal to be monitored. A path to a predefined probe location for monitoring the signal is defined from the resistor using the probe structure.

Claims

1. A method for implementing multiple signals probing of a printed circuit board comprising the steps of:

forming a probe structure on an outside surface of the printed circuit board;

electrically connecting a resistor with a predefined via associated with a signal to be monitored; and

defining a path to a predefined probe location for monitoring said signal from said resistor using said probe structure.

2. A method for implementing multiple signals probing as recited in claim 1 wherein the step of forming said probe structure includes the step of forming a pattern of a plurality of spaced apart stubs to define said probe structure on said outside surface of the printed circuit board.

3. A method for implementing multiple signals probing as recited in claim 2 wherein the step of forming said pattern of said plurality of stubs includes the step of etching an electrically conductive material in said pattern of said plurality of stubs to define said probe structure on said outside surface of the printed circuit board, each stub including an elongated portion extending from at least one pad.

4. A method for implementing multiple signals probing as recited in claim 3 wherein said electrically conductive material includes copper.

5. A method for implementing multiple signals probing as recited in claim 3 wherein the step of electrically connecting said resistor includes the step of placing said resistor between said predefined via associated with said signal to be monitored and said pad of an adjacent one of said plurality of stubs of said probe structure.

6. A method for implementing multiple signals probing as recited in claim 3 wherein the step of defining said path to said predefined probe location for monitoring said signal from said resistor using said probe structure includes the steps of placing zero-ohm shorts between selected ones of said plurality of stubs of said probe structure.

7. A method for implementing multiple signals probing as recited in claim 1 wherein said resistor has a selected high resistance value relative to a characteristic impedance of the printed circuit board at said predefined via associated with said signal to be monitored.

8. A method for implementing multiple signals probing as recited in claim 1 includes the steps of removing said resistor and said path after testing is completed.

9. Apparatus for implementing multiple signals probing of a printed circuit board comprising:

a probe structure formed on an outside surface of the printed circuit board;

a resistor electrically connected with a predefined via associated with a signal to be monitored; and

a path defined to a predefined probe location for monitoring said signal from said resistor using said probe structure.

10. Apparatus for implementing multiple signals probing as recited in claim 9 wherein said probe structure includes an electrically conductive material forming a pattern of a plurality of spaced apart stubs defining said probe structure on said outside surface of the printed circuit board, each stub including an elongated portion extending from at least one pad.

11. Apparatus for implementing multiple signals probing as recited in claim 10 wherein said path is formed by electrically shorting between said pads of selected ones of said plurality of spaced apart stubs.

12. Apparatus for implementing multiple signals probing as recited in claim 9 wherein said resistor and said path are removed after testing is completed.

13. Apparatus for implementing multiple signals probing as recited in claim 9 wherein said probe structure formed on said outside surface of the printed circuit board includes an electrically conductive material etched to define a grid of a plurality of spaced apart stubs defining said probe structure.

14. Apparatus for implementing multiple signals probing as recited in claim 13 wherein said electrically conductive material is copper.

15. Apparatus for implementing multiple signals probing as recited in claim 9 wherein said resistor has a selected high resistance value relative to a characteristic impedance of the printed circuit board at said predefined via associated with said signal to be monitored.