Printed circuit board for sensing voltage drop

• US 7,663,376 B2
• Filed: 08/06/2007
• Issued: 02/16/2010
• Est. Priority Date: 08/06/2007
• Status: Active Grant

• Current Assignee: Lear Corporation
• Original Assignee: Lear Corporation
• Inventors: Fernandez, Jose Gabriel
• Primary Examiner(s): Nguyen; Vincent Q
• Application Number:
  US11/890,386
• Publication Number:
  US 20090039865A1
• Time in Patent Office: 925 Days
• Field of Search: 324/72, 324/76.11, 324/126, 324/117.H, 324/117.R, 324/555, 324/503, 338/32.R
• US Class Current: 324/555
• CPC Class Codes: G01R 1/203 Resistors used for electric measuring, e.g. decade resistors standards, resistors for comparators, series resistors, shunts resistors in general H01C; microwave or radiowave terminations H01P1/26; coupling devices H01R
• CPC Class Codes: G01R 31/364 Battery terminal connectors with integrated measuring arrangements
• CPC Class Codes: H01M 10/06 Lead-acid accumulators semi-lead accumulators H01M10/20
• CPC Class Codes: H01M 10/425 Structural combination with electronic components, e.g. electronic circuits integrated to the outside of the casing printed circuits H05K1/00
• CPC Class Codes: H01R 11/281 for connections to batteries
• CPC Class Codes: H01R 13/6683 with built-in sensor
• CPC Class Codes: H05K 1/0268 for electrical inspection or testing
• CPC Class Codes: H05K 1/167 incorporating printed resistors
• CPC Class Codes: H05K 2201/093 Layout of power planes, ground planes or power supply conductors, e.g. having special clearance holes therein reduction of cross-talk, noise or interference by patterned shielding planes, ground planes or power planes H05K1/0224
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

A printed circuit board (PCB) having capabilities to measure a voltage drop of current flowing therethrough. The PCB may optionally include other capabilities for measuring, calculating, sensing, or other processing of information and data associated with the current flow or other operating conditions associated with the PCB, such as but not limited to those associated with battery monitoring systems.

Claims

1. A multilayer printed circuit board (PCB) for use in transferring current from an input to an output, the PCB comprising:

a first non-conducting plane;

a first conducting plane adhered to the first non-conducting plane, the first conducting plane electrically connected to both of the input and output to transfer current therebetween, the first conducting plane composed of at least a first material having a first resistivity and a second material having a second resistivity such that current flowing between the input and output flows through both of the first material and the second material, wherein the first material is coplanar with the second material for at least an area defined by the first non-conducting plane; and

a processor adhered to the first non-conducting plane and in electrical communication with the first material and configured to measure a voltage drop across the second material.

2. The PCB of claim 1 wherein the second resistivity is greater than the first resistivity.

3. The PCB of claim 2 wherein the first material is copper and the second material is a copper alloy.

4. The PCB of claim 3 wherein the second material is manganin.

5. The PCB of claim 1 wherein the first conducting plane is flat between the input and the output.

6. The PCB of claim 1 wherein the first material is positioned along opposed sides of the second material.

7. The PCB of claim 1 wherein the second material extends widthwise across from one side of the first conducting plane to the other side of the first conducting plane.

8. The PCB of claim 1 wherein the second material defines a gap within the first material that extends widthwise across from one side of the conducting plane to the other side of the first conducting plane, the second material including at least two sections within the gap to define a space between each section and within the gap.

9. The PCB of claim 1 further comprising a second non-conducting plane adhered to the first conducting plane and a second conducting plane adhered to the second non-conducting plane, the second conducting plane composed of at least a third material having a third resistivity and a fourth material having a fourth resistivity, the first material of the first conducting plane being in electrical communication with the third material of the second conducting plane, the processor also being in electrical communication with the third material and configured to measure voltage drop across the second and fourth material.

10. The PCB of claim 9 wherein the first and third materials have the same resistivity and the second and fourth materials have the same resistivity.

11. The PCB of claim 9 wherein the first material is aligned with the third material and the second material is aligned with the fourth material.

12. The PCB of claim 9 wherein current flow through the first conducting plane is equal to current flow through the second conducting plane.

13. The PCB of claim 9 further comprising vias for electrically connecting the first and third materials and the processor.

14. A battery monitoring system for monitoring a battery used to power a number of electronic devices connected to a vehicle chassis within a vehicle, the system comprising:

a battery monitor having a first non-conducting layer and a first conducting layer, the first conducting layer composed of at least a first material having a first resistivity and a second material having a second resistivity, the battery monitor further including a processor in electrical communication with the first material to measure a voltage drop across the second material;

a battery terminal adapter for connecting the first conducting layer to a post of the battery; and

a cable for connecting the first conducting layer to the vehicle chassis such that current flow between the electronic devices and the battery must flow through the first conducting layer.

15. The system of claim 14 wherein the battery monitor further comprising a second non-conducting layer adhered to the first conducting layer and a second conducting layer adhered to the second non-conducting layer, the second conducting layer composed of at least a third material having a third resistivity and a fourth material having a fourth resistivity, the first material of the first conducting layer being in electrical communication with the third material of the second conducting layer, the processor also being in electrical communication with the third material and configured to measure voltage drop across the second and fourth material.

16. The system of claim 15 wherein the battery terminal adapter is welded to the first and second conducting layers.

17. The system of claim 15 wherein the cable is welded to the first and second conducting layers.

18. The system of claim 15 wherein the first and third materials have the same resistivity and the second and fourth materials have the same resistivity.

19. The PCB of claim 18 wherein the first material is aligned with the third material and the second material is aligned with the fourth material.

20. The PCB of claim 18 wherein current flow through the first conducting layer is equal to current flow through the second conducting layer.