Bridge synchronous rectifier

• US 8,320,143 B2
• Filed: 04/14/2009
• Issued: 11/27/2012
• Est. Priority Date: 04/15/2008
• Status: Active Grant

• Current Assignee: Powermat Technologies, Ltd.
• Original Assignee: Powermat Technologies, Ltd.
• Inventors: Leibovitz, Alfred
• Primary Examiner(s): Laxton, Gary L
• Assistant Examiner(s): Quddus, Nusrat
• Application Number:
  US12/423,530
• Publication Number:
  US 20090257259A1
• Time in Patent Office: 1,323 Days
• Field of Search: 363/67, 363/69, 363/71, 363/76, 363/77, 363/84, 363/85, 363/88, 363/125, 363/127, 363/128, 363/89
• US Class Current: 363/89
• CPC Class Codes: H02M 7/217 using semiconductor devices only

Abstract

A current-triggered synchro-rectifier comprising an electronic switch configured to be in its ON setting when the current flowing through its cathode exceeds a predetermined threshold. The electronic switch may include a half-wave rectifier wired to the source terminal and the drain terminal of a MOSFET device, and a current monitor configured to monitor the drain-current flowing through the drain terminal. The current monitor sends a gate signal to the gate terminal such that the MOSFET is switched to its ON state when the drain-current exceeds a first threshold current and the MOSFET is switched to its OFF state when the drain-current falls below a second threshold current. Usefully, the synchro-rectifier may be incorporated into a full-wave rectifier.

Claims

1. A full-wave rectifier configured to convert an AC input to

a DC output comprising;

a first input terminal;

a second input terminal;

a first output terminal; and

a second output terminal;

wherein said full-wave rectifier further comprises;

a first half-wave rectifier comprising;

i. a first MOSFET device having a source terminal wired to said first output terminal, a drain terminal wired to said first input terminal, and a gate terminal;

ii. a fifth half-wave rectifier in parallel with said first MOSFET device, wired to the source terminal and the drain terminal of the first MOSFET device;

iii. a first current monitor configured to monitor a drain-current flowing through the drain terminal of the first MOSFET device and to send a gate signal to the gate terminal of the first MOSFET device such that the first MOSFET device is switched to its ON state when said drain-current exceeds a first threshold current and the first MOSFET device is switched to its OFF state when said drain-current falls below a second threshold current;

a second half-wave rectifier comprising;

i. a first MOSFET device having a source terminal wired to said first output terminal, a drain terminal wired to said first input terminal, and a gate terminal;

ii. a fifth half-wave rectifier in parallel with said first MOSFET device, wired to the source terminal and the drain terminal of the first MOSFET device;

iii. a first current monitor configured to monitor a drain-current flowing through the drain terminal of the first MOSFET device and to send a gate signal to the gate terminal of the first MOSFET device such that the first MOSFET device is switched to its ON state when said drain-current exceeds a first threshold current and the first MOSFET device is switched to its OFF state when said drain-current falls below a second threshold current;

a third half-wave rectifier having one anode wired to said first input terminal and one cathode wired to a second output terminal; and

a fourth half-wave rectifier having one anode wired to said second input terminal and one cathode wired to said second output terminal.

2. The full-wave rectifier of claim 1 wherein at least one the first MOSFET device is configured to be switched between its ON and OFF states in synchrony with the frequency of the input signal.

3. The full-wave rectifier of claim 1 wherein:

said third half-wave rectifiers is configured to be switched between its ON and OFF states in phase with the voltage signal at said second input terminal, and

said fourth half-wave rectifiers is configured to be switched between its ON and OFF states in phase with the voltage signal at said first input terminal.

4. The full-wave rectifier of claim 3 wherein at least one of said third half-wave rectifier and said fourth half-wave rectifier comprises a transistor.

5. The full-wave rectifier of claim 3 wherein at least one of said third half-wave rectifier and said fourth half-wave rectifier electronic switch comprises a MOSFET device.

6. The full-wave rectifier of claim 3 wherein at least one of said third half-wave rectifier and said fourth half-wave rectifier comprises:

a MOSFET device comprising a source terminal, a drain terminal and a gate terminal;

a half-wave rectifier wired to said source terminal and said drain terminal in parallel with said MOSFET device, and

a current monitor configured to monitor a drain-current flowing through said drain terminal and to send a gate signal to said gate terminal such that said MOSFET is switched to its ON state when said drain-current exceeds a first threshold current and said MOSFET is switched to its OFF state when said drain-current falls below a second threshold current.

7. The full-wave rectifier of claim 6 wherein said current monitor comprises a current transformer.

8. The full-wave rectifier of claim 1 incorporated into a power converter.

9. A power converter comprising the full-wave rectifier of claim 1.

10. The full wave rectifier of claim 1 incorporated into an LLC resonant converter.

11. The full-wave rectifier of claim 1 incorporated into an implanted medical device.

12. The full-wave rectifier of claim 1 incorporated into an inductive power receiver comprising a secondary inductor configured to inductively couple with a remote primary inductor.

13. The full-wave rectifier of claim 1 incorporated into a power harvesting device.

14. The full wave rectifier of claim 1 incorporated into a device comprising at least power generator.

15. The full-wave rectifier of claim 14 wherein said power generator is selected from the group consisting of:

at least one solar cell, at least one turbogenerator and at least one fuel-cell.

16. The full-wave rectifier of claim 1 wherein at least one of said fifth half-wave rectifier and said sixth half-wave rectifier comprises a diode.

17. The full wave rectifier of claim 6 wherein said half-wave rectifier comprises a diode.

18. The full-wave rectifier of claim 1 wherein at least one of said first current monitor and said second current monitor comprises a current transformer.