Power supply and DC-DC converter with voltage drop circuit therein

• US 9,350,242 B2
• Filed: 04/22/2014
• Issued: 05/24/2016
• Est. Priority Date: 05/03/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Joon Hwan, Lee, Min Kwang, Chu, Jung Suk, Yang, Soon Bae, Kim, Jae Jin, Lee, Dong Gyu
• Primary Examiner(s): Mehari, Yemane
• Application Number:
  US14/258,573
• Publication Number:
  US 20140327420A1
• Time in Patent Office: 763 Days
• Field of Search: 323282-285
• US Class Current: 1/1
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• 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

A power supply includes a rectifier circuit to rectify power, a smoothing circuit unit to smoothen a voltage of the rectified power, and a voltage drop circuit unit to drop the smoothened voltage. The voltage drop circuit unit includes an electric charge storage circuit to output the voltage-dropped voltage, a resonance circuit to receive first current from the smoothing circuit unit and to supply second current to the electric charge storage circuit, and a current interruption circuit to control the first current and the second current using zero current switching for performing switching when current does not flow using a resonance circuit.

Claims

1. A power supply comprising:

a smoothing circuit unit to receive a voltage and to smoothen the voltage; and

a voltage drop circuit unit to drop the smoothened voltage,

wherein the voltage drop circuit unit comprises;

an electric charge storage circuit to output the dropped smoothened voltage;

a resonance circuit to receive first current from the smoothing circuit unit and to supply second current to the electric charge storage circuit;

a switching circuit, the switching circuit including;

a first switch to control the first current such that the first current is supplied to the resonance circuit and the electric charge storage circuit via the first switch; and

a second switch to control the second current such that the second current is supplied to the electric charge storage circuit via the second switch; and

a rectifier circuit, the rectifier circuit including;

a first diode to pass the first current and to shut off the second current; and

a second diode to pass the second current and to shut off the first current.

2. The power supply according to claim 1, further comprising a voltage drop controller to control the first switch and the second switch.

3. The power supply according to claim 2, wherein the voltage drop controller alternately opens and closes the first switch and the second switch.

4. The power supply according to claim 3, wherein the voltage drop controller opens and closes the first switch and the second switch at a same period as a resonance period of the resonance circuit.

5. The power supply according to claim 1, wherein the first switch and the second switch are connected in series to each other.

6. The power supply according to claim 5, wherein the first diode and the second diode are connected in series to each other.

7. The power supply according to claim 6, wherein the resonance circuit is disposed between a node to which the first switch and the second switch are connected and a node to which the first diode and the second diode are connected.

8. The power supply according to claim 7, wherein the resonance circuit comprises at least one capacitor and at least one inductor.

9. The power supply according to claim 1, further comprising an initial charging circuit to initially charge the electric charge storage circuit.

10. The power supply according to claim 9, wherein the initial charging circuit is disposed in series between one side of the electric charge storage circuit and one side of the switching circuit.

11. The power supply according to claim 10, wherein the initial charging circuit comprises a charged current limiting circuit to limit an amount of initial charged current for charging the electric charge storage circuit, and a first initial charging switch to interrupt initial charged current supplied to the electric charge storage circuit.

12. The power supply according to claim 11, wherein the initial charging circuit further comprises a second initial charging switch to interrupt initial charged current supplied to a resonance capacitor included in the resonance circuit.

13. The power supply according to claim 12, wherein the second initial charging switch is disposed between the other side of the electrical charge storage circuit and the resonance capacitor included in the resonance circuit.

14. A voltage drop circuit for dropping a voltage of a power source, the voltage drop circuit comprising:

an electric charge storage circuit unit to output the dropped voltage;

a resonance circuit unit to receive first current from the power source and to supply second current to the electric charge storage circuit;

a switching circuit, the switching circuit including;

a first switch to control the first current such that the first current is supplied to the resonance circuit unit and the electric charge storage circuit unit via the first switch; and

a second switch to control the second current such that the second current is supplied to the electric charge storage circuit unit via the second switch; and

a rectifier circuit, the rectifier circuit including;

a first diode to pass the first current and to shut off the second current; and

a second diode to pass the second current and to shut off the first current.

15. The voltage drop circuit according to claim 14, further comprising a voltage drop controller to control the first switch and the second switch.

16. The voltage drop circuit according to claim 15, wherein the voltage drop controller alternately opens and closes the first switch and the second switch.

17. The voltage drop circuit according to claim 16, wherein the voltage drop controller opens and closes the first switch and the second switch at the same period as a resonance period of the resonance circuit.

18. The voltage drop circuit according to claim 14, further comprising an initial charging circuit to initially charge the electric charge storage circuit.

19. The voltage drop circuit according to claim 18, wherein the initial charging circuit comprises a charged current limiting circuit to limit an amount of initial charged current for charging the electric charge storage circuit, and a first initial charging switch to interrupt initial charged current supplied to the electric charge storage circuit.

20. A voltage drop circuit for dropping a voltage of a power source, the voltage drop circuit comprising:

at least one electric charge storage circuit unit to output the dropped voltage;

at least one resonance circuit unit to receive first current from the power source and to supply second current to the electric charge storage circuit;

a switching circuit including a first switch to interrupt the first current and a second switch to interrupt the second current;

a rectifier circuit to rectify the first current and the second current; and

a voltage drop controller to control the switching circuit,

wherein the rectifier circuit comprises;

a first plurality of diodes connected in series to pass the first current and to shut off the second current when the first switch is controlled to be closed and the second switch is controlled to be opened; and

a second plurality of diodes connected in series to shut off the first current and to pass the second current when the first switch is controlled to be open and the second switch is controlled to be closed.

21. The voltage drop circuit according to claim 20, wherein the first switch receives a first control signal from the voltage drop controller to interrupt the first current and the second switch receives a second control signal from the voltage drop controller to interrupt the second current.

22. The voltage drop circuit according to claim 20, wherein:

the at least one resonance circuit comprises;

a resonance inductor; and

a resonance capacitor,

and a first end of the resonance circuit is connected to a first node disposed between the first switch and the second switch, and a second end of the resonance circuit is connected to a second node disposed between one of the first plurality of diodes and one of the second plurality of diodes.

23. The voltage drop circuit according to claim 22, wherein the resonance capacitor is connected to the first node and the resonance inductor is connected to the second node.

24. The voltage drop circuit according to claim 20, wherein the at least one electric charge storage circuit unit comprises:

a first electric charge storage circuit connected in series with a second electric charge storage circuit,

wherein a first node disposed between the first electric charge storage circuit and the second electric charge storage is connected to a second node disposed between one of the first plurality of diodes and one of the second plurality of diodes.

25. The voltage drop circuit according to claim 20, wherein the at least one resonance circuit comprises:

a first resonance circuit including a resonance inductor and a first resonance capacitor; and

a second resonance circuit including the resonance inductor and a second resonance capacitor,

wherein a first end of the first resonance circuit is connected to a first node disposed between the first switch and the second switch, and a second end of the first resonance circuit is connected to a second node disposed between one of the first plurality of diodes and one of the second plurality of diodes, and

a first end of the second resonance circuit is connected to the first node, and a second end of the second resonance circuit is connected to a third node disposed between one of the first plurality of diodes and one of the second plurality of diodes.