Process for manufacturing a composite polymeric circuit protection device

• US 6,854,176 B2
• Filed: 12/12/2001
• Issued: 02/15/2005
• Est. Priority Date: 09/14/1999
• Status: Expired due to Term

• Current Assignee: Littelfuse Incorporated
• Original Assignee: Tyco Electronics Corporation (TE Connectivity Ltd. (United Kingdom))
• Inventors: Galla, Matthew P., Chandler, Daniel A., Toth, James, Hetherton, Scott, Bruguier, Thomas, Daering, Randy, Montoya, Wayne
• Primary Examiner(s): Vo, Peter
• Assistant Examiner(s): Nguyen, Donghai D.
• Application Number:
  US10/017,670
• Publication Number:
  US 20020162214A1
• Time in Patent Office: 1,161 Days
• Field of Search: 29/253.5, 294/12, 29416-418, 296/021, 296/091, 296/23, 298/30, 298/32, 298/46, 298/54, 219/50, 320/134, 320/137, 320/127, 338/25.R, 338/322, 338307-309, 338321-313, 338/328, 338/332, 361/58, 361/106, 361/306.1
• US Class Current: 29/623
• CPC Class Codes: H01C 1/1406 Terminals or electrodes formed on resistive elements having positive temperature coefficient
• CPC Class Codes: H01C 13/02 Structural combinations of resistors impedance networks per se H03H
• CPC Class Codes: H01C 17/006 adapted for manufacturing resistor chips
• CPC Class Codes: H01C 17/28 adapted for applying terminals
• CPC Class Codes: H01C 7/021 formed as one or more layers or coatings
• CPC Class Codes: H01C 7/027 consisting of conducting or semi-conducting material dispersed in a non-conductive organic material
• CPC Class Codes: H01C 7/18 comprising a plurality of layers stacked between terminals
• CPC Class Codes: H05K 3/0052 Depaneling, i.e. dividing a panel into circuit boards; Working of the edges of circuit boards
• CPC Class Codes: H05K 3/403 Edge contacts; Windows or holes in the substrate having plural connections on the walls thereof H05K3/4092 takes precedence
• CPC Class Codes: Y10T 29/49107 Fuse making
• CPC Class Codes: Y10T 29/49126 Assembling bases
• CPC Class Codes: Y10T 29/49128 Assembling formed circuit to base
• CPC Class Codes: Y10T 29/4913 Assembling to base an electrical component, e.g., capacitor, etc.
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49169 Assembling electrical component directly to terminal or elongated conductor
• CPC Class Codes: Y10T 29/49798 Dividing sequentially from leading end, e.g., by cutting or breaking

Abstract

A process for manufacturing a composite polymeric circuit protection device in which a polymeric assembly is provided and is then subdivided into individual devices (2). The assembly is made by providing first and second laminates (7,8), each of which includes a laminar polymer element having at least one conductive surface, providing a pattern on at least one of the conductive surfaces on one laminate, securing the laminates in a stack (1) in a desired configuration, at least one conductive surface of at least one of the laminates forming an external conductive surface (3) of the stack, and making a plurality of electrical connections (31,51) between a conductive surface of the first laminate and a conductive surface of the second laminate. The laminar polymer elements may be PTC conductive polymer compositions, so that the individual devices made by the process exhibit PTC behavior. Additional electrical components may be attached directly to the surface of the device or assembly.

Claims

1. A process for manufacturing a composite polymeric circuit protection device, said process comprising

(1) providing a polymeric assembly comprising

(a) providing first and second laminates, each of which comprises a laminar polymer element having at least one conductive surface,

(b) providing a pattern of conductive material on at least one of the conductive surfaces on both the first and second laminates;

(c) securing the laminates in a stack in a desired configuration, conductive surfaces of the laminates comprising two external conductive surfaces of the stack;

(d) making a plurality of electrical connections between a conductive surface of the first laminate and a conductive surface of the second laminate, and

(e) attaching a plurality of electrical components to both external conductive surfaces of the stack; and

(2) subdividing the assembly into individual devices each of which comprises (i) at least one electrical connection, and (ii) at least one electrical component.

2. A process according to claim 1 wherein the electrical component is attached to a permanent electrical connection pad.

3. A process according to claim 2 wherein the electrical connection pad comprises a solderable material.

4. A process according to claim 1 wherein the electrical component is attached to a reconnectable contact pad.

5. A process according to claim 4 wherein the reconnectable contact pad comprises gold, palladium, or palladium nickel alloy.

6. A process according to claim 1, wherein an additional conductive layer is added to at least part of at least one of the external conductive surfaces to form the electrical connection pad or the reconnectable contact pad.

7. A process according to claim 1 wherein the laminar polymer element in the first laminate comprises a PTC conductive polymer composition.

8. A process for manufacturing a composite polymeric circuit protection device, said process comprising

(1) providing a polymeric assembly comprising

(a) providing first and second laminates, each of which comprises a laminar polymer element having at least one conductive surface, the laminar polymer element in the first laminate comprising a PTC conductive polymer composition and the laminar polymer element in the second laminate comprising a dielectric material;

(b) providing a pattern of conductive material on at least one of the conductive surfaces on one laminate;

(c) securing the laminates in a stack in a desired configuration, at least one conductive surface of at least one of the laminates comprising an external conductive surface of the stack,

(d) making a plurality of electrical connections between a conductive surface of the first laminate and a conductive surface of the second laminate, and

(e) attaching a plurality of electrical components to the external conductive surface of the stack; and

(2) subdividing the assembly into individual devices each of which comprises (i) at least one electrical connection, and (ii) at least one electrical component.

9. A process according to claim 8 wherein the assembly further comprises a third laminate which comprises a laminar element which is a dielectric, the second and third laminates positioned on the top and bottom of the first laminate.

10. A process for manufacturing a composite polymeric circuit protection device, said process comprising

(1) providing a polymeric assembly comprising

(a) providing first and second laminates, each of which comprises a laminar polymer element having at least one conductive surface, the laminar polymer element in the first laminate comprising a PTC conductive polymer composition and the laminar polymer element in the second laminate comprising a dielectric material,

(b) providing a pattern of conductive material on at least one of the conductive surfaces on one laminate;

(c) securing the laminates in a stack in a desired configuration, at least one conductive surface of at least one of the laminates comprising an external conductive surface of the stack,

(d) making a plurality of electrical connections between a conductive surface of the first laminate and a conductive surface of the second laminate;

(2) subdividing the assembly into individual devices each of which comprises at least one electrical connection; and

(3) attaching at least one electrical component to an external conductive surface of each device.

11. A process according to claim 10 wherein the assembly further comprises a third laminate which comprises a laminar element which is a dielectric, the second and third laminates positioned on the top and bottom of the first laminate.

12. A process for manufacturing a composite polymeric circuit protection device, said process comprising

(1) providing a polymeric assembly comprising

(a) providing a first laminate which comprises a laminar polymer element comprising a conductive polymer composition, said laminar polymer element having at least one conductive surface,

(b) providing a second laminate which comprises a laminar polymer element comprising an insulating polymer composition, said laminar polymer element having at least one conductive surface,

(c) providing a pattern of conductive material on at least one of the conductive surfaces on one laminate;

(d) securing the laminates in a stack in a desired configuration, at least one conductive surface of at least one of the laminates comprising an external conductive surface of the stack,

(e) making a plurality of electrical connections between a conductive surface of the first laminate and a conductive surface of the second laminate, and

(f) providing an additional conductive layer on at least part of at least one of the external conductive surfaces to form an electrical connection pad or a reconnectable contact pad; and

(2) subdividing the assembly into individual devices each of which comprises (i) at least one electrical connection, and (ii) at least one electrical connection pad or reconnectable contact pad.

13. A process according to claim 12 wherein each device comprises at least one electrical connection pad on one external surface and at least one reconnectable contact pad on the other external surface.