Galvanic isolator

• US 7,791,900 B2
• Filed: 08/28/2006
• Issued: 09/07/2010
• Est. Priority Date: 08/28/2006
• Status: Expired due to Fees

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Fouquet, Julie E., Trott, Gary R.
• Primary Examiner(s): PERT, EVAN T
• Application Number:
  US11/512,034
• Publication Number:
  US 20080061631A1
• Time in Patent Office: 1,471 Days
• Field of Search: 336/182, 336/185, 336/200, 336/206, 361/803, 361/804
• US Class Current: 361/803
• CPC Class Codes: H01F 17/0006 Printed inductances printed coils for dynamo-electric machines H02K3/26; printed circuits H05K
• CPC Class Codes: H01F 17/0013 with stacked layers
• CPC Class Codes: H01F 19/08 Transformers having magnetic bias, e.g. for handling pulses
• CPC Class Codes: H01F 2019/085 Transformer for galvanic isolation
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/40 Structural association with built-in electric component, e.g. fuse
• CPC Class Codes: H01L 25/16 the devices being of types provided for in two or more different main groups of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. forming hybrid circuits
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: H03H 7/46 Networks for connecting several sources or loads, working on different frequencies or frequency bands, to a common load or source for use in multiplex transmission systems H04J1/00
• CPC Class Codes: H03H 7/52 One-way transmission networks, i.e. unilines
• CPC Class Codes: H04B 5/005 for isolation purposes
• CPC Class Codes: H04B 5/0093 with one coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils
• CPC Class Codes: H04B 5/75 for isolation purposes
• CPC Class Codes: H04L 25/0266 Arrangements for providing Galvanic isolation, e.g. by means of magnetic or capacitive coupling

Abstract

A galvanic isolator having a split circuit element, a polymeric substrate, a transmitter and receiver is disclosed. The split circuit element has first and second portions, the first portion being disposed on a first surface of the substrate and the second portion being disposed a second surface of the substrate. The transmitter receives an input signal and couples a signal derived from the input signal to the first portion. The receiver is connected to the second portion of the circuit element and generates an output signal that is coupled to an external circuit. The galvanic isolator can be economically fabricated on conventional printed circuit board substrates and flexible circuit substrates.

Claims

1. A galvanic isolator comprising:

a first circuit board comprising a first surface and a second surface, wherein a circuit is disposed on said first surface;

a second circuit board comprising a first surface and a second surface, wherein a circuit is disposed on said first surface;

a substrate comprising an insulating polymeric or polymeric/inorganic layer having first and second surfaces, said first and second surfaces being on opposite sides of said substrate, said first side of said first circuit board being adjacent said first side of said substrate and said first side of said second circuit board being adjacent said second side of said substrate;

a transmitter that receives an input signal and couples an electronic signal derived from said input signal to said first portion; and

a receiver connected to said second portion that generates an output signal that is coupled to an external circuit.

2. The galvanic isolator of claim 1 wherein said first circuit board contacts said first surface of said substrate and second circuit board contacts said second surface of said substrate.

3. The galvanic isolator of claim 1 further comprising an insulating protective layer covering said first circuit board.

4. The galvanic isolator of claim 3 wherein said protective layer comprises a polymeric layer having an adhesive coating that is in contact with said first circuit board.

5. The galvanic isolator of claim 1 wherein said circuit on said first circuit board comprises a coil.

6. The galvanic isolator of claim 1 wherein said polymeric layer comprises a first sub-layer having said first surface, an insulating sub-layer, and a second sub-layer having said second surface, said first and second sub-layers sandwiching said insulating sub-layer and being bonded thereto.

7. The galvanic isolator of claim 6 wherein said substrate comprises a first planar region and a second planar region at an angle greater than 0 with respect to said first planar region, said first circuit board and said second circuit board being disposed across said second planar region.

8. The galvanic isolator of claim 1 wherein said substrate is flexible.

9. The galvanic isolator of claim 1 wherein said substrate comprises a material chosen from the group consisting of polyamide, epoxy, and fiber glass impregnated with epoxy.

10. The galvanic isolator of claim 1 further comprising a planar conducting sheet surrounding said first circuit board and said second circuit board and spaced apart therefrom by a distance greater than 10 mils.