Resistor with temperature coefficient of resistance (TCR) compensation

• US 9,400,294 B2
• Filed: 11/03/2014
• Issued: 07/26/2016
• Est. Priority Date: 09/04/2009
• Status: Active Grant

• Current Assignee: Vishay Dale Electronics, LLC (Vishay Intertechnology Incorporated)
• Original Assignee: Vishay Dale Electronics, LLC (Vishay Intertechnology Incorporated)
• Inventors: Smith, Clark L., Bertsch, Thomas L., Wyatt, Todd L., Veik, Thomas L.
• Primary Examiner(s): LEE, KYUNG S
• Application Number:
  US14/531,505
• Publication Number:
  US 20150054531A1
• Time in Patent Office: 631 Days
• Field of Search: 338/22.R
• US Class Current: 1/1
• 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 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 19/32 Compensating for temperature change
• CPC Class Codes: H01C 1/00 Details
• CPC Class Codes: H01C 1/148 the terminals embracing or surrounding the resistive element H01C1/142 takes precedence
• CPC Class Codes: H01C 17/232 Adjusting the temperature coefficient; Adjusting value of resistance by adjusting temperature coefficient of resistance
• CPC Class Codes: H01C 17/28 adapted for applying terminals
• CPC Class Codes: H01C 7/06 including means to minimise changes in resistance with changes in temperature
• CPC Class Codes: Y10T 29/49082 Resistor making
• CPC Class Codes: Y10T 29/49101 Applying terminal

Abstract

A current sense resistor and a method of manufacturing a current sensing resistor with temperature coefficient of resistance (TCR) compensation are disclosed. The resistor has a resistive strip disposed between two conductive strips. A pair of main terminals and a pair of voltage sense terminals are formed in the conductive strips. A pair of rough TCR calibration slots is located between the main terminals and the voltage sense terminals, each of the rough TCR calibration slots have a depth selected to obtain a negative starting TCR value observed at the voltage sense terminals. A fine TCR calibration slot is formed between the pair of voltage sense terminals.

Claims

1. A resistor with temperature coefficient of resistance (TCR) compensation, the resistor comprising:

a resistive strip disposed between two conductive strips;

a calibration slot formed within the resistive strip;

first and second main terminals formed in the conductive strips; and

first and second voltage sense terminals formed in inner areas of the conductive strips, wherein the first voltage sense terminal comprises a first and second leg positioned between the first main terminal and the resistive strip and the second voltage sense terminal comprises a first leg and second leg positioned between the second main terminal and the resistive strip.

2. The resistor of claim 1, wherein the first leg of the first voltage sense terminal and second voltage sense terminal each have a length that extends substantially orthogonal to a main current path.

3. The resistor of claim 1, wherein the second leg of the first voltage sense terminal and second voltage sense terminal each have a length that extends substantially parallel to a main current path.

4. The resistor of claim 1, wherein a length of the first leg and a length of the second leg of the first voltage sense terminal are equal.

5. The resistor of claim 1, wherein a length of the first leg and a length of the second leg of the first voltage sense terminal are different.

6. The resistor of claim 1, wherein the first leg and second leg of the first and second voltage sense terminals intersect at a right angle.

7. The resistor of claim 6, wherein an inner vertex of the intersection of the first and second leg of the first and second voltage sense terminals has a rectangular profile.

8. The resistor of claim 6, wherein an outer vertex of the intersection of the first and second leg of the first and second voltage sense terminals has a rounded profile.

9. The resistor of claim 1, wherein the first leg and second leg of the first and second voltage sense terminals intersect at an acute angle.

10. The resistor of claim 1, wherein the first leg and second leg of the first and second voltage sense terminals intersect at an obtuse angle.

11. The resistor of claim 1, wherein the calibration slot has a depth selected to obtain a TCR value observed at the first and second voltage sense terminals that approaches zero.

12. A method of manufacturing a resistor with temperature coefficient of resistance (TCR) compensation, the method comprising:

forming a resistive strip disposed between two conductive strips;

forming a calibration slot within the resistive strip;

forming first and second main terminals in the conductive strips; and

forming first and second voltage sense terminals in inner areas of the conductive strips, wherein the first voltage sense terminal comprises a first and second leg positioned between the first main terminal and the resistive strip and the second voltage sense terminal comprises a first leg and second leg positioned between the second main terminal and the resistive strip.

13. The method of claim 12, wherein the first leg of the first voltage sense terminal and second voltage sense terminal each have a length that extends substantially orthogonal to a main current path.

14. The method of claim 12, wherein the second leg of the first voltage sense terminal and second voltage sense terminal each have a length that extends substantially parallel to a main current path.

15. The method of claim 12, wherein a length of the first leg and a length of the second leg of the first voltage sense terminal are equal.

16. The method of claim 12, wherein the calibration slot has a depth selected to obtain a TCR value observed at the first and second voltage sense terminals that approaches zero.

17. A resistor with temperature coefficient of resistance (TCR) compensation, the resistor comprising:

a resistive strip disposed between a first conductive strip and a second conductive strip;

a calibration slot formed within the resistive strip;

first and second main terminals formed in the first and second conductive strips;

a first slot formed in an interior area of the first conductive strip, the first slot defining the dimensions of a first voltage sense terminal;

a second slot formed in an interior area of the second conductive strip, the second slot defining the dimensions of a second voltage sense terminal.

18. The resistor of claim 17, wherein the first slot comprises a first leg extending generally parallel to the main current path, and the second slot comprises a first leg extending generally parallel to the main current path.

19. The resistor of claim 18, wherein at least one of the first slot or the second slot further comprises a second leg extending generally perpendicular to the main current path.

20. The resistor of claim 17, wherein the first slot has at least one generally U-shaped end portion.

21. The resistor of claim 17, wherein the second slot has at least one generally U-shaped end portion.

22. A resistor with temperature coefficient of resistance (TCR) compensation, the resistor comprising:

a resistive strip having a first edge, second edge, first side and second side, the resistive strip disposed between a first conductive strip on the first side of the resistive strip, and a second conductive strip on the second side of the resistive strip;

a first main terminal and a first voltage sense terminal formed contiguously in the first conductive strip, the first voltage sense terminal positioned adjacent the first edge of the resistive strip;

a second main terminal and a second voltage sense terminal formed contiguously in the second conductive strip, the second voltage sense terminal positioned adjacent the first edge of the resistive strip;

a first calibration slot formed in the conductive strip between the first voltage sense terminal and the first main terminal, the first calibration slot having a first end and a second end, the second end of the first calibration slot positioned further away from the resistive strip than the first end of the first calibration slot;

a second calibration slot formed in the conductive strip between the second voltage sense terminal and the second main terminal, the second calibration slot having a first end and a second end, the second end of the second calibration slot positioned further away from the resistive strip than the first end of the second calibration slot; and

,

a third calibration slot formed at the first edge of the resistive strip between the first and second voltage sense terminals.

23. The resistor of claim 22, wherein the first calibration slot and the second calibration are formed only in the conductive strips.

24. The resistor of claim 22, wherein the third calibration slot does not meet either the first calibration slot or the second calibration slot.

25. The resistor of claim 22, wherein the third calibration slot is formed longitudinally in the resistive strip.

26. The resistor of claim 22, further comprising a fourth calibration slot formed at the second edge of the resistive strip between the first and second main terminals.