Signal isolator having inductive and capacitive signal coupling

Patent metadata

Field	Value
Publication number	US-10074939-B1
Application number	US-201715671357-A
Country	US
Kind code	B1
Filing date	Aug 8, 2017
Priority date	Aug 8, 2017
Publication date	Sep 11, 2018
Grant date	Sep 11, 2018

Abstract

Methods and apparatus for a signal isolator having inductive and capacitive coupling. In embodiments, magnetic and electric fields are coupled by coils and capacitive plates. In embodiments, a floating plate can enable a top and bottom capacitive plate to be offset from each other.

First claim

What is claimed is:

1. A signal isolator, comprising:
a first coil having first and second ends;
a first plate coupled to the first end of the first coil;
a second plate coupled to the second end of the first coil, where the first and/or second plate is configured to be coupled to a drive circuit;
a second coil inductively coupled to the first coil;
a third plate capacitively coupled to the first plate;
a fourth plate capacitively coupled to the second plate;
at least one isolation layer between the first and second coils and between the first and second plates and the third and fourth plates;
a receive module including a first receive circuit coupled to the third and fourth plates and a second receive circuit to receive a signal on the second coil; and
a processing module to generate an output signal corresponding to a signal transmitted by the drive circuit from signals received by the first and second receive circuits.

2. The signal isolator according to claim 1 , wherein the first and second coils are substantially planar coils.

3. The signal isolator according to claim 1 , wherein the first plate and second plate corresponds to bond pads.

4. The signal isolator according to claim 1 , wherein the first and/or second plates and the first coil are substantially co-planar.

5. The signal isolator according to claim 1 , further including a floating plate between at least the first and third plates.

6. The signal isolator according to claim 5 , wherein the floating plate is capacitively coupled with the first and third plates.

7. The signal isolator according to claim 5 , wherein the floating plate distributes charge across the floating plate.

8. A method for providing a signal isolator, comprising:
employing a first coil having first and second ends;
employing a first plate coupled to the first end of the first coil;
employing a second plate coupled to the second end of the first coil, where the first and/or second plate is configured to be coupled to a drive circuit;
employing a second coil inductively coupled to the first coil;
employing a third plate capacitively coupled to the first plate;
employing a fourth plate capacitively coupled to the second plate;
employing at least one isolation layer between the first and second coils and between the first and second plates and the third and fourth plates;
employing a receive module including a first receive circuit coupled to the third and fourth plates and a second receive circuit to receive a signal on the second coil; and
employing a processing module to generate an output signal corresponding to a signal transmitted by the drive circuit from signals received by the first and second receive circuits.

9. The method according to claim 8 , wherein the first and second coils are substantially planar coils.

10. The method according to claim 8 , wherein the first plate and second plate correspond to bond pads.

11. The method according to claim 8 , wherein the first and/or second plates and the first coil are substantially co-planar.

12. The method according to claim 8 , further including a floating plate between at least the first and third plates.

13. The method according to claim 12 , wherein the floating plate is capacitively coupled with the first and third plates.

14. The method according to claim 12 , wherein the floating plate distributes charge across the floating plate.

15. A signal isolator, comprising:
a first coil means;
a first plate means for capacitive coupling coupled to the first coil means;
a second plate means coupled to the first coil means, where the first and/or second plate means is configured to be coupled to a drive circuit;
a second coil means inductively coupled to the first coil means;
a third plate means capacitively coupled to the first plate means;
a fourth plate means capacitively coupled to the second plate means;
at least one isolation layer between the first and second coil means and between the first and second plate means and the third and fourth plate means;
a receive means including a first receive circuit coupled to the third and fourth plate means and a second receive circuit to receive a signal on the second coil means; and
a processing means to generate an output signal corresponding to a signal transmitted by the drive circuit from signals received by the first and second receive circuits.

16. The signal isolator according to claim 15 , wherein the first and second coil means are substantially planar coils.

17. The signal isolator according to claim 15 , wherein the first plate means and second plate means correspond to bond pads.

18. The signal isolator according to claim 15 , wherein the first and/or second plates means and the first coil are substantially co-planar.

19. The signal isolator according to claim 1 , further including a floating plate between at least the first and third plate means.

20. The signal isolator according to claim 19 , wherein the floating plate is capacitively coupled with the first and third plate means.

21. The signal isolator according to claim 19 , wherein the floating plate distributes charge across the floating plate.

Assignees

• Allegro Microsystems Llc

Inventors

• Briano Robert A

Classifications

• H10W90/811

  Multiple chips on leadframes · CPC title

• H10W90/753

  between laterally-adjacent chips · CPC title

• H10W72/07554

  changes in dispositions · CPC title

• H10W72/981

  Auxiliary members, e.g. spacers · CPC title

• H10W72/932

  Plan-view shape, i.e. in top view · CPC title