Methods and apparatus for isolation barrier with integrated magnetics for high power modules

Patent metadata

Field	Value
Publication number	US-2020105458-A1
Application number	US-201916700739-A
Country	US
Kind code	A1
Filing date	Dec 2, 2019
Priority date	Dec 18, 2015
Publication date	Apr 2, 2020
Grant date	—

Abstract

For isolation barrier with magnetics, an apparatus includes an isolation laminate including a dielectric core having a first surface and a second surface opposed to the first surface; at least one conductive layer configured as a first transformer coil overlying the first surface; a first dielectric layer surrounding the at least one conductive layer; a first magnetic layer overlying the at least one conductive layer; at least one additional conductive layer configured as a second transformer coil overlying the second surface; a second dielectric layer surrounding the at least one additional conductive layer; and a second magnetic layer overlying the at least one additional conductive layer. Methods for forming the isolation barriers and additional apparatus arrangements are also described.

First claim

What is claimed is:

1 . An apparatus, comprising:
an isolation laminate, comprising:
a dielectric core having a first surface and a second surface opposed to the first surface;
at least one conductive layer configured as a first transformer coil overlying the first surface;
a first dielectric layer surrounding the at least one conductive layer;
a first magnetic layer overlying the at least one conductive layer;
at least one additional conductive layer configured as a second transformer coil overlying the second surface;
a second dielectric layer surrounding the at least one additional conductive layer; and
a second magnetic layer overlying at least one additional conductive layer.

2 . The apparatus of claim 1 , and further comprising:
a conductive layer forming at least one EMI shield overlying one of the first surface and the second surface of the dielectric core; and a dielectric material surrounding the magnetic shield and insulating the at least one EMI shield from the first transformer coil and the second transformer coil.

3 . The apparatus of claim 1 , and further comprising:
a leadframe having a die attach pad; and the isolation laminate disposed upon the die attach pad and in thermal contact with the die attach pad through one of the first and second magnetic layers.

4 . The apparatus of claim 1 wherein the dielectric core further comprises BT resin.

5 . The apparatus of claim 1 wherein the first dielectric layer further comprises prepreg material.

6 . The apparatus of claim 1 wherein the first and second magnetic layers are formed from powdered magnetic material in a sintering operation.

7 . The apparatus of claim 6 wherein the powdered magnetic material comprises ferrite material.

8 . The apparatus of claim 1 wherein the first magnetic layer further comprises magnetic material having a permeability of greater than about 1.

9 . The apparatus of claim 1 wherein the first magnetic layer further comprises a ferrous material.

10 . The apparatus of claim 1 wherein the first magnetic layer further comprises material including at least one of nickel and zinc.

11 . The apparatus of claim 1 wherein the at least one conductive layer further comprises copper or other electrical conductor.

12 . A packaged integrated circuit, comprising:
a leadframe having first and second portions for placing a first semiconductor circuit and a second semiconductor circuit; and an isolation laminate mounted on a third portion of the leadframe and isolated from at least one of the first portion and the second portion, comprising:
a dielectric core having a first surface and a second surface opposed to the first surface;
at least one conductive layer configured as a first transformer coil overlying the first surface;
a first dielectric layer surrounding the at least one conductive layer;
a first magnetic layer overlying the at least one conductive layer;
at least one additional conductive layer configured as a second transformer coil overlying the second surface;
a second dielectric layer surrounding the at least one additional conductive layer; and
a second magnetic layer overlying the at least one additional conductive layer.

13 . The packaged integrated circuit of claim 12 , and further comprising:
a first circuit disposed on the first portion of the leadframe and coupled to the first transformer coil; and a second circuit disposed on the second portion of the leadframe and coupled to the second transformer coil; wherein the first circuit and the second circuit are galvanically isolated from one another and signals from the first circuit are coupled to the second circuit by the first and second transformer coils.

14 . The packaged integrated circuit of claim 12 , wherein the isolation laminate further comprises:
a conductive layer forming at least one EMI shield overlying one of the first surface and the second surface of the dielectric core; and a dielectric material surrounding the EMI shield and insulating the EMI shield from the first transformer coil and the second transformer coil.

15 . The packaged integrated circuit of claim 14 , wherein the isolation laminate further comprises:
a second conductive layer forming at least one additional EMI shield overlying one of the first surface and the second surface of the dielectric core; and a dielectric material surrounding the at least one additional EMI shield and insulating the at least one additional EMI shield from the first transformer coil, the second transformer coil, and the at least one EMI shield.

16 . The packaged integrated circuit of claim 12 , wherein the first magnetic layer comprises a magnetic material having a permeability of greater than about 1.

17 . The packaged integrated circuit of claim 12 , wherein the first magnetic layer comprises a material that is one chosen from the group consisting essentially of ferrite material and metal-based magnetic material.

18 . The packaged integrated circuit of claim 12 , and further comprising encapsulation material surrounding the leadframe and the isolation laminate.

19 . A method, comprising:
providing a dielectric core material having a first surface and a second surface opposing the first surface; forming in a first conductive layer a first transformer coil overlying the first surface of the dielectric core; forming a first dielectric layer surrounding the first conductive layer; forming a first magnetic layer overlying the first transformer coil; forming in a second conductive layer a second transformer coil overlying the second surface of the dielectric core; forming a second dielectric layer surrounding the second transformer coil; and forming a second magnetic layer overlying the second transformer coil.

20 . The method of claim 19 , wherein forming the first magnetic layer further comprises sintering a magnetic powdered material.

Assignees

• Texas Instruments Inc

Inventors

• Massolini Roberto Giampiero
• Khanolkar Vijaylaxmi
• Mullenix Joyce
• Miftakhutdinov Rais

Classifications

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title

• B22F7/06

  of composite workpieces or articles from parts, e.g. to form tipped tools {(B22F7/002 takes precedence)} · CPC title

• B22F3/10

  Sintering only · CPC title

• H01F41/046

  structurally combined with ferromagnetic material · CPC title

• C22C2202/02

  Magnetic · CPC title