Ultra low standby consumption in a high power power converter

• US 8,369,111 B2
• Filed: 08/02/2010
• Issued: 02/05/2013
• Est. Priority Date: 08/02/2010
• Status: Expired due to Fees

• Current Assignee: Power Integrations Incorporated
• Original Assignee: Power Integrations Incorporated
• Inventors: Balakrishnan, Balu, Matthews, David Michael Hugh
• Primary Examiner(s): Vu, Bao Q
• Application Number:
  US12/848,617
• Publication Number:
  US 20120026759A1
• Time in Patent Office: 918 Days
• Field of Search: 363/21.12, 363/21.15, 363/21.16, 363/21.17, 363/56.09, 363/56.1, 363/97, 363/131
• US Class Current: 363/21.15
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/0048 Circuits or arrangements for reducing losses using snubbers H02M1/34
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: H02M 3/33523 with galvanic isolation between input and output of both the power stage and the feedback loop
• 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 converter with low power consumption during a standby operating condition. An example power controller includes a main converter coupled to a dc input of the power converter to control a transfer of energy from the dc input of the power converter to a main output of the power converter. A standby converter is also included and is coupled to the dc input of the power converter to control a transfer of energy from the dc input of the power converter to a standby output of the power converter during a standby operating condition of the power converter. A standby circuit is also included and is coupled to the dc input of the power converter and coupled to the main converter. The standby circuit decouples the main converter from the dc input of the power converter during the standby operating condition of the power converter.

Claims

1. A power converter, comprising:

a main converter coupled to a dc input of the power converter to control a transfer of energy from the input of the power converter to a main output of the power converter;

a standby converter coupled to the dc input of the power converter to control a transfer of energy from the dc input of the power converter to a standby output of the power converter during a standby operating condition of the power converter; and

a standby circuit coupled to the dc input of the power converter and coupled to the main converter, the standby circuit to decouple the main converter from the dc input of the power converter during the standby operating condition of the power converter.

2. The power converter of claim 1 further comprising a main bulk capacitor included in the main converter, the main bulk capacitor coupled to the dc input of the power converter and coupled to the standby circuit, the standby circuit to decouple the main bulk capacitor from the dc input of the power converter during the standby operating condition of the power converter.

3. The power converter of claim 2 further comprising a standby bulk capacitor included in the standby converter, the standby bulk capacitor coupled to the dc input of the power converter, the standby bulk capacitor to remain coupled to the dc input of the power converter during the standby operating condition of the power converter.

4. The power converter of claim 1 wherein the standby circuit comprises a switch coupled to the main converter and coupled to the power converter input, the switch to decouple the main converter from the dc input of the power converter during the standby operating condition of the power converter.

5. The power converter of claim 4 wherein the switch comprises a transistor coupled to the main converter and coupled to the power converter dc input, wherein the transistor is coupled to operate in its saturation region as the power converter transitions from the standby operating condition to a normal operating condition.

6. The power converter of claim 4 wherein the standby circuit includes a standby switch control circuit coupled to the switch to control a current through the switch to limit an in-rush current into a main bulk capacitor included in the main converter as the power converter transitions from the standby operating condition to a normal operating condition.

7. The power converter of claim 6 wherein the standby switch control circuit coupled to the switch comprises a capacitor coupled to a gate terminal and a drain terminal of the switch.

8. The power converter of claim 1 further comprising a secondary side control circuit coupled to the standby output of the power converter and coupled to the standby circuit, the secondary side control circuit coupled to generate a system standby signal coupled to be received by the standby circuit to indicate the standby operating condition of the power converter.

9. The power converter of claim 8 further comprising an optocoupler coupled between the secondary side control circuit and the standby circuit.

10. The power converter of claim 1 wherein the main converter comprises a step down converter coupled between the dc input of the power converter and the main output of the power converter.

11. The power converter of claim 10 wherein the main converter further comprises a boost converter coupled between the dc input of the power converter and the step down converter.

12. The power converter of claim 1 wherein the standby converter is coupled to the dc input of the power converter through the main converter.

13. The power converter of claim 1 further comprising a rectifier coupled to receive an ac signal from an ac source, wherein the rectifier is coupled to generate a rectified signal at the dc input of the power converter.

14. A method for controlling a power converter, comprising:

switching a power switch of a main converter of a power converter to control a transfer of energy from a dc input of a power converter to a main output of the power converter during a normal operating condition of the power converter;

disabling substantially all current through the main converter of the power converter from the dc input of the power converter during a standby operating condition of the power converter; and

switching a power switch of a standby converter of the power converter to control a transfer of energy from the dc input of the power converter to a standby output of the power converter during the normal operating condition and during the standby operation condition of the power converter.

15. The method for controlling the power converter of claim 14 further comprising disabling a main bulk capacitor included in the main converter of the power converter from receiving substantially all current from the dc input of the power converter during the standby operating condition of the power converter.

16. The method for controlling the power converter of claim 15 further comprising allowing a standby bulk capacitor included in the standby converter of the power converter to continue receiving current from the dc input of the power converter during the normal operating condition and the standby operating condition of the power converter.

17. The method for controlling the power converter of claim 15 further comprising limiting an in-rush current into the main bulk capacitor included in the main converter of the power converter as the power converter transitions from the standby operating condition to the normal operating condition.

18. The method for controlling the power converter of claim 17 wherein limiting the in-rush current into the main bulk capacitor included in the main converter of the power converter comprises operating a transistor coupled to the input of a power converter and the main converter in its saturation region as the power converter transitions from the standby operating condition to the normal operating condition.

19. The method for controlling the power converter of claim 17 wherein limiting the in-rush current into the main bulk capacitor included in the main converter of the power converter comprises controlling a slew rate of a transistor coupled to the dc input of a power converter and the main converter as the power converter transitions from the standby operating condition to the normal operating condition.

20. The method for controlling the power converter of claim 14 further comprising generating a system standby signal with a secondary side control circuit coupled to the standby output of the power converter to indicate the standby operating condition to a standby circuit coupled to the dc input of a power converter and the main converter.

21. The method for controlling the power converter of claim 20 further comprising electrically isolating the secondary side control circuit from the standby circuit.