Switch mode power supply and method

• US 20020141210A1
• Filed: 03/30/2001
• Published: 10/03/2002
• Est. Priority Date: 03/30/2001
• Status: Active Grant

• Current Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Li, Qiong, Lee, Nai-Chi, Glannopoulos, Demetri
• Granted Patent: US 6,510,066 B2
• Time in Patent Office: Days
• US Class Current: 363/97
• CPC Class Codes: H02M 1/0012 Control circuits using digital or numerical techniques in DC/DC converters H02M3/157, H02M3/33515; in DC-AC converters H02M7/53873
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/009 having two or more independently controlled outputs for DC-DC converter with intermediate AC H02M3/33561
• 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 switch mode power supply (SMPS) and method are provided. In particular, the present invention provides an SMPS in which data is encoded by manipulating voltage pulses on a primary side. The manipulated voltage pulses are then transferred over a transformer to a secondary side. Secondary side pulses generated in response to the primary side pulses are sensed and decoded by a detector. The present invention allows data to be transferred from the primary side to the secondary side without affecting output voltages.

Claims

1. A switch mode power supply (SMPS) having a primary side and a secondary side separated by a transformer, comprising:

a controller that regulates the generation of pulses on the primary side; and

an encoding system for encoding data by changing a frequency of a set of the pulses on the primary side.

2. The SMPS of claim 1, wherein the change in frequency results in a decrease in pulse frequency and an increase in pulse width so that average power output is maintained.

3. The SMPS of claim 1, wherein the change in frequency results in an increase in pulse frequency and a decrease in pulse width so that average power output is maintained.

4. The SMPS of claim 1, further comprising a detector on the secondary side for sensing the encoded data by detecting manipulations in secondary side pulses, wherein the secondary side pulses are generated in response to the primary side pulses.

5. The SMPS of claim 4, wherein the detector is a variable pulse-width detector, and wherein the detector further decodes the encoded data.

6. The SPMS of claim 1, further comprising a receiver on the primary side.

7. The SMPS of claim 6, wherein the receiver is selected from the group consisting of a wireless interface or an infrared interface.

8. The SMPS of claim 1, wherein the secondary side further comprises a main load and a microprocessor.

9. The SMPS of claim 1, further comprising an opto-coupler, wherein the opto-coupler transfers feedback from the secondary side to the primary side.

10. The SMPS of claim 1, wherein the set comprises a plurality of sequential pulses.

11. A switch mode power supply (SMPS), comprising:

a primary side including a main power source, a controller, and a receiver, wherein the controller regulates the generation of pulses on the primary side and encodes data by changing a pulse width for a set of the pulses;

a secondary side for receiving power and the encoded data from the primary side, wherein the secondary side includes a main load, a microprocessor, and a detector, and wherein the detector senses the encoded data by detecting manipulations in secondary side pulses generated in response to the primary side pulses; and

a transformer separating the primary side from the secondary side.

12. The SMPS of claim 11 further comprising an opto-coupler for separating the primary side from the secondary side.

13. The SMPS of claim 12, wherein the transformer and the opto-coupler separate the main power source from the main load and the microprocessor.

14. The SMPS of claim 11, wherein the width change results in a decrease in pulse width and an increase in pulse frequency.

15. The SMPS of claim 11, wherein the width change results in an increase in pulse width and a decrease in pulse frequency.

16. The SMPS of claim 11, wherein the detector is a variable pulse-width detector, and wherein the detector decodes the encoded data by detecting a change in width of the pulses.

17. The SMPS of claim 11, wherein the opto-coupler transfers feedback from the secondary side to the primary side.

19. The method of claim 18, wherein the changing step comprises the step of decreasing a width and increasing a frequency of a set of the pulses on the primary side to encode data.

20. The method of claim 18, wherein the changing step comprises the step of increasing a width of and decreasing a frequency of a set of the pulses on the primary side to encode data.

21. The method of claim 18, wherein the changing step further comprises assigning a value to each pulse width.

22. The method of claim 18, wherein the decoding step comprises the steps of:

detecting a starting point of a data set;

detecting a width of pulses generated on the secondary side in response to the pulses on the primary side; and

assigning a data value based on the detected width.

18. A method for transferring data from a primary side to a secondary side of a switch mode power supply (SMPS), comprising the steps of:

changing a width of pulses on the primary side to encode data;

transferring the encoded data to the secondary side;

sensing the encoded data on the secondary side; and

decoding the encoded data.