Inductor with thermally stable resistance

• US 8,975,994 B2
• Filed: 02/15/2013
• Issued: 03/10/2015
• Est. Priority Date: 09/27/2006
• Status: Active Grant

• Current Assignee: Vishay Dale Electronics, LLC (Vishay Intertechnology Incorporated)
• Original Assignee: Vishay Dale Electronics (Vishay Intertechnology Incorporated)
• Inventors: Hansen, Thomas T., Hoffman, Jerome J., Schafer, Timothy, Schade, Nicholas J., Lange, David, Smith, Clark, Brune, Rod
• Primary Examiner(s): NGUYEN, TUYEN T
• Application Number:
  US13/768,039
• Publication Number:
  US 20130285784A1
• Time in Patent Office: 753 Days
• Field of Search: 336/178, 336233-234, 336/200, 336/192
• US Class Current: 336/192
• CPC Class Codes: H01F 17/04 with magnetic core
• CPC Class Codes: H01F 2017/048 with encapsulating core, e.g. made of resin and magnetic powder
• CPC Class Codes: H01F 27/292 Surface mounted devices
• CPC Class Codes: H01F 27/40 Structural association with built-in electric component, e.g. fuse
• CPC Class Codes: H01F 3/08 made from powder powder coatings on sheets H01F3/02; on strips or ribbons H01F3/04; on wires H01F3/06
• CPC Class Codes: H01F 41/02 for manufacturing cores, coils, or magnets H01F41/14 takes precedence; for dynamo-electric machines H02K15/00

Abstract

An inductor includes an inductor body having a top surface and a first and second opposite end surfaces. There is a void through the inductor body between the first and second opposite end surfaces. A thermally stable resistive element positioned through the void and turned toward the top surface to forms surface mount terminals which can be used for Kelvin type sensing. Where the inductor body is formed of a ferrite, the inductor body includes a slot. The resistive element may be formed of a punched resistive strip and provide for a partial turn or multiple turns. The inductor may be formed of a distributed gap magnetic material formed around the resistive element. A method for manufacturing the inductor includes positioning an inductor body around a thermally stable resistive element such that terminals of the thermally stable resistive element extend from the inductor body.

Claims

1. An inductor comprising:

a thermally stable resistive element;

an inductor body having a top surface and first and second opposite end surfaces;

the inductor body comprising a distributed gap magnetic material pressed over the thermally stable resistive element;

wherein opposite ends of the resistive element are each turned along outer sides of the first and second opposite end surfaces toward the top surface of the inductor body and have ends that overlap the top surface of the inductor body to form opposite surface mount terminals, each surface mount terminal including a larger terminal for current carrying and a smaller terminal for Kelvin-type current sensing.

2. The inductor of claim 1 wherein the thermally stable resistive element is formed of a non-ferrous metallic alloy.

3. The inductor of claim 1 wherein the thermally stable resistive element comprises a non-ferrous metallic alloy comprising nickel and copper.

4. The inductor of claim 1 wherein the thermally stable resistive element comprises iron, chromium, and aluminum.