EP-4738399-A1 - MULTI-CHANNEL ISOLATION TRANSFORMER AND GATE DRIVER STRUCTURES

Abstract

Systems, structures, packages, circuits, and methods provide multi-channel isolation transformer and gate driver structures with one or more primary and multiple secondary coils. The transformer structures include magnetic cores configured for use with multiple channels providing galvanic isolation for each channel. The channels can pass control (data) and/or power signals/pulses. One or more integrated circuits may be included with transformer packages, structures, and modules. In some examples, structure, chip packages, or modules may include one or more galvanically isolated gate drivers and/or other high voltage circuits.

Inventors

• THOMPSON, ANDREW
• Balakrishnan, Manoj
• DUIGAN, JOSEPH
• KEOGH, ANDREW BERNARD
• VU, Tue T.

Assignees

• Allegro MicroSystems, LLC

Dates

Publication Date

20260506

Application Date

20250819

Claims (20)

1. A multi-channel magnetic isolation structure comprising: a magnetic core disposed on a substrate, wherein the magnetic core includes soft ferromagnetic material; at one or more primary coils configured about the magnetic core; a plurality of secondary coils configured about the magnetic core; one or more primary integrated circuits (IC) corresponding connected to the one or more primary coils; and a plurality of secondary ICs connected to the plurality of secondary coils, respectively; wherein the structure is configured to transfer power and/or data between the one or more primary coils and the plurality of secondary coils.
2. The structure of claim 1, wherein the plurality of secondary ICs comprises one or more gate drivers configured to control a solid state switch.
3. The structure of claim 1, wherein the magnetic core comprises first and second lateral regions and a plurality of apertures separated by at least one central region.
4. The structure of claim 1, wherein the one or more primary coils comprise a complementary drive coil configured about a lateral region of the magnetic core and a simultaneous drive coil configured about a first central region of the magnetic core.
5. A method of making a multi-channel magnetic isolation structure, the method comprising: providing a magnetic core disposed on a substrate, wherein the substrate includes soft ferromagnetic material; providing one or more primary coils configured about the magnetic core; providing a plurality of secondary coils configured about the magnetic core; providing one or more primary integrated circuits (ICs) connected to the at least one primary coil; and providing a plurality of secondary ICs connected to the plurality of secondary coils, respectively; wherein the structure is configured to transfer power and/or data between the one or more primary coils and the plurality of secondary coils.
6. The method of claim 5, or the structure of claim 1, wherein the structure is configured to transfer data between the plurality of secondary coils.
7. The method of claim 5, or the structure of claim 1, wherein the one or more primary coils comprises a plurality of primary coils, and wherein the structure is configured to transfer data between the plurality of primary coils.
8. The method of claim 5, wherein the plurality of secondary ICs comprises one or more gate drivers configured to control a solid state switch.
9. The method of claim 8, or the structure of claim 4, wherein the solid state switch comprises a field effect transistor (FET).
10. The method of claim 8, or the structure of claim 4, wherein the solid state switch comprises a power MOSFET.
11. The method of claim 5, or the structure of claim 1, wherein the one or more primary ICs correspond in number with the one or more primary coils.
12. The method of claim 5, wherein the magnetic core comprises first and second lateral regions and a plurality of apertures separated by at least one central region.
13. The method of claim 12, or the structure of claim 3, wherein the at least one central region has a width about twice the width of the first lateral region and/or the second lateral region.
14. The method of claim 12, or the structure of claim 3, wherein the at least one central region has a width about equal to the width of the first lateral region and/or the second lateral region.
15. The method of claim 12, or the structure of claim 3, wherein the one or more primary coils comprise a first primary coil that is configured about the at least one central region, and further comprising first and second flux steering coils configured about the first and second lateral regions of the magnetic core, respectively.
16. The method of claim 12, or the structure of claim 3, wherein the one or more primary coils comprise first and second primary coils configured about magnetic core on opposite sides of the at least one central region, wherein each of the first and second primary coils is configured to be selectively shorted.
17. The method of claim 5, wherein the one or more primary coils comprise a complementary drive coil configured about a lateral region of the magnetic core and a simultaneous drive coil configured about a first central region of the magnetic core.
18. The method of claim 17, or the structure of claim 4, wherein the complementary drive coil is configured about two lateral portions of the magnetic core.
19. The method of claim 5, or the structure of claim 1, wherein the substrate comprises a printed circuit board (PCB).
20. The method of claim 5, or the structure of claim 1, wherein the substrate comprises a printed circuit board (PCB) including an aperture configured to receive the magnetic core.

Description

BACKGROUND Solid state switches typically include a transistor structure. The controlling electrode of the switch, usually referred to as its gate (or base), is typically controlled (driven) by a switch drive circuit, sometimes also referred to as gate drive circuit. Such solid state switches are typically voltage-controlled, turning on when the gate voltage exceeds a manufacturer-specific threshold voltage by a margin, and turning off when the gate voltage remains below the threshold voltage by a margin. Switch drive circuits typically receive their control instructions from a controller such as a pulse-width-modulated (PWM) controller via one or more switch driver inputs. Switch drive circuits deliver their drive signals directly (or indirectly via networks of active and passive components) to the respective terminals of the switch (gate and source). Some electronic systems, including ones with solid state switches, have employed galvanic isolation to prevent undesirable DC currents flowing from one side of an isolation barrier to the other. Such galvanic isolation can be used to separate circuits in order to protect users from coming into direct contact with hazardous voltages. Various transmission techniques are available for signals to be sent across galvanic isolation barriers including optical, capacitive, and magnetic coupling techniques. Magnetic coupling typically relies on use of a transformer to magnetically couple circuits on the different sides of the transformer, typically referred to as the primary and secondary sides, while also providing galvanic separation of the circuits. Transformers used for magnetic-coupling isolation barriers typically utilize a magnetic core to provide a magnetic path to channel flux created by the currents flowing in the primary and secondary sides of the transformer. Magnetic-coupling isolation barriers have been shown to have various drawbacks, including manufacturing problems, for integrated circuit (IC) packages due to the included magnetic core. SUMMARY Aspect of the present disclosure are directed to multi-channel transformer structures, assemblies, packages, and related circuits and methods. One general aspect of the present disclosure includes a multi-channel magnetic isolation structure. The multi-channel magnetic isolation structure can include: a magnetic core disposed on a substrate, where the magnetic core includes soft ferromagnetic material; at one or more primary coils configured about the magnetic core; a plurality of secondary coils configured about the magnetic core; one or more primary integrated circuits (ICs) corresponding connected to the one or more primary coils; and a plurality of secondary ICs connected to the plurality of secondary coils, respectively; where the structure is configured to transfer power and/or data between the one or more primary coils and the plurality of secondary coils. Implementations may include one or more of the following features. The structure can be configured to transfer data between the plurality of secondary coils. The one or more primary coils may include a plurality of primary coils, and where the structure can be configured to transfer data between the plurality of primary coils. The plurality of secondary ICs may include one or more gate drivers configured to control a solid state switch. The solid state switch may include a field effect transistor (FET). The FET may include a power MOSFET. The one or more primary ICs may correspond in number with the one or more primary coils. The magnetic core may include first and second lateral regions and a plurality of apertures separated by at least one central region. The at least one central region may have a width about twice the width of the first lateral region and/or the second lateral region. The central region may have a width about equal to the width of the first lateral region and/or the second lateral region. The one or more primary coils may include a first primary coil that is configured about the at least one central region and may include first and second flux steering coils configured about the first and second lateral regions of the magnetic core, respectively. The one or more primary coils may include first and second primary coils configured about magnetic core on opposite sides of the at least one central region, where each of the first and second primary coils is configured to be selectively shorted. The one or more primary coils may include a complementary drive coil configured about a lateral region of the magnetic core and one or more simultaneous drive coils configured about a first central region of the magnetic core. The complementary drive coil may be configured about two lateral portions of the magnetic core. The substrate may include a printed circuit board (PCB). The PCB may include an aperture configured to receive the magnetic core. The substrate may include a lead frame. Another general aspect includes a method of making a multi-c