Magnetically coupled galvanically isolated communication using lead frame

• US 9,331,004 B2
• Filed: 04/16/2015
• Issued: 05/03/2016
• Est. Priority Date: 11/14/2012
• Status: Active Grant

• Current Assignee: Power Integrations Incorporated
• Original Assignee: Power Integrations Incorporated
• Inventors: Balakrishnan, Balu, Matthews, David Michael Hugh
• Primary Examiner(s): VU, HUNG K
• Application Number:
  US14/688,257
• Publication Number:
  US 20150221583A1
• Time in Patent Office: 383 Days
• Field of Search: 257/666, 257/676, 257/678, 257/687, 257/690, 257/787, 257/E23.031
• US Class Current: 1/1
• CPC Class Codes: H01L 2224/05599 Material
• CPC Class Codes: H01L 2224/45099 Material
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/48465 the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/4903 Connectors having different sizes, e.g. different diameters
• CPC Class Codes: H01L 2224/4911 the connectors being bonded to at least one common bonding area, e.g. daisy chain
• CPC Class Codes: H01L 2224/49111 the connectors connecting two common bonding areas, e.g. Litz or braid wires
• CPC Class Codes: H01L 2224/49171 Fan-out arrangements
• CPC Class Codes: H01L 2224/85399 Material
• CPC Class Codes: H01L 23/28 Encapsulations, e.g. encapsulating layers, coatings, e.g. for protectionH01L23/552 takes precedence; insulating layers for contacts or interconnections H01L23/5329
• CPC Class Codes: H01L 23/3107 the device being completely enclosed
• CPC Class Codes: H01L 23/48 Arrangements for conducting electric current to or from the solid state body in operation, e.g. leads, terminal arrangements ; Selection of materials therefor
• CPC Class Codes: H01L 23/49541 Geometry of the lead-frame
• CPC Class Codes: H01L 23/49575 Assemblies of semiconductor devices on lead frames
• CPC Class Codes: H01L 23/552 Protection against radiation, e.g. light or electromagnetic waves
• CPC Class Codes: H01L 23/58 Structural electrical arrangements for semiconductor devices not otherwise provided for , e.g. in combination with batteries H01L23/49593, H01L23/49596 take precedence
• CPC Class Codes: H01L 24/48 of an individual wire connector
• CPC Class Codes: H01L 24/49 of a plurality of wire connectors
• CPC Class Codes: H01L 25/0655 the devices being arranged next to each other
• CPC Class Codes: H01L 25/18 : the devices being of types provided for in two or more different subgroups of the same main group of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N
• 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 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/12032 : Schottky diode
• CPC Class Codes: H01L 2924/13091 : Metal-Oxide-Semiconductor Field-Effect Transistor [MOSFET]
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/14253 : Digital-to-analog converter [DAC]
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/19107 : off-chip wires
• CPC Class Codes: H01L 2924/30107 : Inductance
• CPC Class Codes: H02M 3/003 : Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H02M 3/33507 : with automatic control of the output voltage or current, e.g. flyback converters H02M3/33561, H02M3/33569 take precedence
• CPC Class Codes: H02M 3/33523 : with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/33592 : having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H02M 7/003 : Constructional details, e.g. physical layout, assembly, wiring or busbar connections
• CPC Class Codes: H02M 7/2176 : comprising a passive stage to generate a rectified sinusoidal voltage and a controlled switching element in series between such stage and the output
• CPC Class Codes: H04B 5/26 : using coils
• CPC Class Codes: H04B 5/72 : for local intradevice communication
• CPC Class Codes: Y02B 70/10 : Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Abstract

An integrated circuit package includes an encapsulation and a lead frame. A portion of the lead frame is disposed within the encapsulation. The lead frame includes a first conductor forming a first conductive loop. A second conductor is galvanically isolated from the first conductor. The second conductor forms a second conductive loop proximate to and magnetically coupled to the first conductive loop to provide a magnetic communication link between the first and second conductors. A signal that is transmitted from a transmit circuit coupled to the first conductor is coupled to be received through the magnetic communication link by a receive circuit coupled to the second conductor.

Claims

1. An integrated circuit package, comprising:

an encapsulation; and

a lead frame, a portion of the lead frame disposed within the encapsulation, the lead frame including;

a first conductor forming a first conductive loop;

a second conductor galvanically isolated from the first conductor, wherein the second conductor forms a second conductive loop proximate to and magnetically coupled to the first conductive loop to provide a magnetic communication link between the first and second conductors, wherein a signal transmitted from a transmit circuit coupled to the first conductor is received through the magnetic communication link by a receive circuit coupled to the second conductor; and

a first bond wire disposed within the encapsulation and coupling together portions of the first conductive loop.

2. The integrated circuit package of claim 1 wherein the transmit circuit is coupled to transmit a transmitter current having rising and falling slopes to induce a pulsating voltage coupled to be received by the receive circuit.

3. The integrated circuit package of claim 2 wherein an amplitude of the pulsating voltage is positive during a rising time of the transmitter current, and wherein the amplitude of the pulsating voltage is negative during a falling time of the transmitter current, wherein the receive circuit includes a comparator coupled to be responsive to the amplitude of the pulsating voltage.

4. The integrated circuit package of claim 1 further comprising a second bond wire disposed within the encapsulation and coupling together portions of the second conductive loop.

5. The integrated circuit package of claim 1 wherein magnetically coupled portions of the first and second conductive loops are disposed substantially in a same plane.

6. The integrated circuit package of claim 1 wherein the first and second conductive loops each consist of one turn.

7. The integrated circuit package of claim 1 wherein substantial portions of the first and second conductive loops are encapsulated in a molded non-ferrous insulating material.

8. The integrated circuit package of claim 1 wherein the receive circuit is disposed within the integrated circuit package, and wherein the receive circuit is coupled to and completes the first conductive loop.

9. The integrated circuit package of claim 1 wherein the receive circuit is included in a first integrated circuit die disposed within the integrated circuit package, wherein the first integrated circuit die is coupled to and completes the first conductive loop.

10. The integrated circuit package of claim 1 wherein the receive circuit is included in a first integrated circuit die mounted on the lead frame, wherein the first integrated circuit die is coupled to and completes the first conductive loop.

11. The integrated circuit package of claim 1 wherein the transmit circuit is disposed within the integrated circuit package, and wherein the transmit circuit is coupled to the second conductive loop.

12. The integrated circuit package of claim 11 wherein the transmit circuit is included in a second integrated circuit die disposed within the integrated circuit package, wherein the second integrated circuit die is coupled to the second conductive loop.

13. The integrated circuit package of claim 11 wherein the transmit circuit is included in a second integrated circuit die mounted on the lead frame, wherein the second integrated circuit die is coupled to the second conductive loop.

14. The integrated circuit package of claim 1 further comprising a first transceiver circuit disposed within the integrated circuit package, wherein the first transceiver circuit includes the transmit circuit coupled to the first conductive loop, wherein the integrated circuit package further comprises a second transceiver circuit disposed within the integrated circuit package, wherein the second transceiver circuit includes the receive circuit coupled to the second conductive loop.

15. The integrated circuit package of claim 1 wherein the first conductor is coupled to a first reference ground and wherein the second conductor is coupled to a second reference ground, wherein the first reference ground and the second reference ground are electrically isolated from one another.