Bus bar for power distribution on a printed circuit board

• US 8,469,724 B1
• Filed: 12/30/2011
• Issued: 06/25/2013
• Est. Priority Date: 12/30/2011
• Status: Active Grant

• Current Assignee: Lenovo International Limited (Lenovo Group Ltd.)
• Original Assignee: International Business Machines Corporation
• Inventors: Barnette, Jamaica L., Clemo, Raymond M.
• Primary Examiner(s): Paumen, Gary F.
• Application Number:
  US13/340,808
• Publication Number:
  US 20130171843A1
• Time in Patent Office: 543 Days
• Field of Search: 439/86, 439/91
• US Class Current: 439/86
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: H01R 12/7088 Arrangements for power supply
• CPC Class Codes: H01R 13/2414 conductive elastomers
• CPC Class Codes: H01R 13/6683 with built-in sensor
• CPC Class Codes: H01R 2201/20 for testing or measuring purposes
• CPC Class Codes: H01R 25/164 Connecting locations formed by flush mounted apparatus

Abstract

A bus bar distributes power to a plurality of electronic components supported on a printed circuit board. One embodiment of the bus bar comprises a plurality of compressible contact pads made from an electronically conductive polymer, spaced along the bus bar for contacting conductive contacts that are coupled to a power domain or individual electronic component. The pads may be secured to the bus bar and the conductive traces using an electronically conductive epoxy adhesive. Rivets may then be used to secure the bus bar to the printed circuit board and compress the pads, which conform to the printed circuit board to make a reliable electrical connection with the conductive traces. The bus bar further comprises a plurality of current sense points disposed adjacent to the pads for measuring the amount of current provided to each power domain.

Claims

1. An apparatus, comprising:

a rigid, electronically conductive bus bar;

a plurality of electronically conductive polymer contact pads secured to the bus bar and spaced apart along the length of the bus bar, wherein the plurality of electronically conductive polymer contact pads are compressible.

2. The apparatus of claim 1, wherein the plurality of electronically conductive polymer contact pads are secured to the bus bar with an electronically conductive adhesive.

3. The apparatus of claim 1, further comprising:

a plurality of fasteners for securing the bus bar to a printed circuit board and compressing the electronically conductive polymer contact pads against contacts on the printed circuit board.

4. The apparatus of claim 1, further comprising:

first and second current sense points secured to the bus bar on opposing sides of each electronically conductive polymer contact pad.

5. The apparatus of claim 4, wherein the current sense points include an electronically conductive polymer material.

6. The apparatus of claim 1, wherein a first pad of the plurality of electronically conductive polymer contact pads comprises a composition having a lower electrical resistance than the other electronically conductive polymer contact pads, wherein the first pad forms an input for contact with a power supply input contact.

7. The apparatus of claim 6, wherein the composition of the first pad comprises aluminum microbeads coated with silver.

8. The apparatus of claim 4, further comprising:

an RFID tag secured to the bus bar, wherein the RFID tag stores data about the resistance of the bus bar between the first and second current sense points on opposing sides of each of the electronically conductive polymer contact pads.

9. The apparatus of claim 1, wherein the plurality of electronically conductive polymer contact pads are equally spaced along the length of the bus bar.

10. A system, comprising:

a printed circuit board supporting a plurality of electronic components, wherein each of the electronic components are electrically connected to one of a plurality of electronically conductive contacts disposed in a linear arrangement on the printed circuit board;

a rigid, electronically conductive bus bar extending over the plurality of electronically conductive contacts;

a plurality of electronically conductive polymer contact pads secured to the bus bar and spaced apart along the length of the bus bar, wherein the plurality of electronically conductive polymer contact pads are compressible; and

one or more fasteners securing the bus bar to the printed circuit board, wherein the one or more fasteners compress each of the plurality of electronically conductive polymer contact pads into electrical contact with one of the plurality of electronically conductive contacts on the printed circuit board.

11. The system of claim 10, wherein the plurality of electronically conductive polymer contact pads are secured to the bus bar with an electronically conductive adhesive.

12. The system of claim 10, further comprising:

first and second current sense points secured to the bus bar on opposing sides of each electronically conductive polymer contact pad.

13. The system of claim 12, wherein the current sense points include an electronically conductive polymer material.

14. The system of claim 10, further comprising:

a power supply providing power to a power supply contact on the printed circuit board, wherein a first pad of the plurality of electronically conductive polymer contact pads comprises a composition having a lower electrical resistance than the other electronically conductive polymer contact pads, wherein the first pad forms an input for contact with the power supply contact.

15. The system of claim 14, wherein the composition of the first pad comprises aluminum microbeads coated with silver.

16. The system of claim 14, wherein the composition of the other electronically conductive polymer contact pads comprise nickel graphite.

17. The system of claim 12, further comprising:

an RFID tag secured to the bus bar, wherein the RFID tag stores data about the resistance of the bus bar between the first and second current sense points on opposing sides of each of the electronically conductive polymer contact pads.

18. The system of claim 10, wherein the plurality of electronically conductive polymer contact pads are equally spaced along the length of the bus bar.

19. The system of claim 10, wherein the fasteners are rivets, wherein each rivet extends through a hole in the bus bar and a hole through the printed circuit board.

20. The system of claim 10, further comprising:

a controller in electronic communication with the first and second current sense points, wherein the controller has access to a database storing predetermined resistance parameters for the bus bar between the first and second current sense point, and wherein the controller executes control logic to determine the current passing through each of the plurality of electronically conductive contact pads.