POWER CONTROL DEVICE AND DISPLAY DEVICE INCLUDING THE SAME

• US 20140143560A1
• Filed: 03/11/2013
• Published: 05/22/2014
• Est. Priority Date: 11/19/2012
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Sung-Cheon Park
• Inventors: KWON, Soon-Gi, PARK, Sung-Cheon
• Granted Patent: US 9,552,030 B2
• Time in Patent Office: Days
• US Class Current: 713/300
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: G06F 1/3287 by switching off individual functional units in the computer system
• CPC Class Codes: G06F 1/3296 by lowering the supply or operating voltage
• CPC Class Codes: G09G 2330/02 Details of power systems and of start or stop of display operation
• CPC Class Codes: G09G 3/2092 Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto suitable for both CRT and flat panel G09G5/003; specific for a CRT G09G1/165
• CPC Class Codes: H02M 1/0025 Arrangements for modifying reference values, feedback values or error values in the control loop of a converter
• CPC Class Codes: H02M 1/32 Means for protecting converters other than automatic disconnection
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: H02M 3/1588 comprising at least one synchronous rectifier element H02M3/1582, H02M3/1584 take precedence
• 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 controller includes an inductor coupled to an input terminal to which an input voltage is input, a first switch coupled between the inductor and a first power source voltage output terminal, a second switch coupled between the inductor and a ground, a switch controller controlling a voltage output to the first power source voltage output terminal by controlling duties of the first and second switches according to a feedback voltage input to a feedback terminal corresponding to a voltage output to the first power source voltage output terminal, and a diode coupled between the first power source voltage output terminal and the feedback terminal, and preventing a voltage of the first power source voltage output terminal from increasing higher than a breakdown voltage of the first and second switches.

Claims

1. A power controller, comprising:

an inductor coupled to an input terminal to which an input voltage is input;

a first switch coupled between the inductor and a first power source voltage output terminal;

a second switch coupled between the inductor and a ground;

a switch controller controlling a voltage output to the first power source voltage output terminal by controlling duties of the first and second switches according to a feedback voltage input to a feedback terminal corresponding to a voltage output to the first power source voltage output terminal; and

a diode coupled between the first power source voltage output terminal and the feedback terminal, and preventing a voltage of the first power source voltage output terminal from increasing higher than a breakdown voltage of the first and second switches.

2. The power controller as claimed in claim 1, wherein a threshold voltage of the diode corresponds to a voltage difference between the voltage of the first power source voltage output terminal and the feedback voltage when the voltage of the first power source voltage output terminal is lower by a predetermined level than the breakdown voltage of the first and second switches.

3. The power controller as claimed in claim 2, wherein, when a voltage difference between the voltage of the first power source voltage output terminal and the feedback voltage reaches the threshold voltage of the diode, the feedback terminal is coupled to the first power source voltage output terminal through the diode.

4. The power controller as claimed in claim 1, further comprising a first differential amplifier including a first input terminal to which the feedback voltage is input, a second input terminal to which a first reference voltage is input, and an output terminal outputting an over-voltage protection signal that corresponds to a voltage difference between the feedback voltage and the first reference voltage.

5. The power controller as claimed in claim 4, further comprising a third switch coupled between the first switch and the first power source voltage output terminal, wherein the switch controller controls turning on and off of the third switch according to the over-voltage protection signal.

6. The power controller as claimed in claim 1, further comprising a first resistor and a second resistor coupled in series between the feedback terminal and a ground and by which a voltage corresponding to a voltage difference between the feedback voltage and a ground voltage is divided.

7. The power controller as claimed in claim 6, further comprising a second differential amplifier including a first input terminal to which a voltage divided between the first resistor and the second resistor is input, a second input terminal to which a second reference voltage is input, and an output terminal outputting a voltage error signal that corresponds to a voltage difference between the divided voltage and the second reference voltage.

8. The power controller as claimed in claim 7, further comprising a third differential amplifier including a first input terminal to which a first pulse width control signal is input, a second input terminal to which the voltage error signal is input, and an output terminal outputting a second pulse width control signal that corresponds to a voltage difference between the first pulse width control signal and the voltage error signal.

9. The power controller as claimed in claim 8, wherein the switch controller controls the duties of the first and second switches according to the second pulse width control signal.

10. The power controller as claimed in claim 1, further comprising a first capacitor including:

a first electrode coupled to the first power source voltage output terminal, and

a second electrode coupled to a ground.

11. The power controller as claimed in claim 1, further comprising a second capacitor including:

a first electrode coupled to a second power source voltage terminal having a low level voltage relative to a high level voltage of the first power source voltage output terminal, and

a second electrode coupled to a ground.

12. A display device, comprising:

a plurality of pixels; and

a power controller supplying a first power source voltage and a second power source voltage to the plurality of pixels,

wherein the power controller outputs the first power source voltage to a first power source voltage output terminal by converting an input voltage, controls the first power source voltage by controlling a duty of a switch according to a feedback voltage input through a feedback voltage corresponding to the first power source voltage, and prevents the first power source voltage from increasing higher than a breakdown voltage of the switch using a diode coupled between the first power source voltage output terminal and the feedback terminal.

13. The display device of claim 12, wherein:

the power controller includes an inductor coupled to an input terminal to which the input voltage is input, and

the switch includes;

a first switch coupled between the inductor and the first power source voltage output terminal, and

a second switch coupled between the inductor and a ground.

14. The display device of claim 13, wherein a threshold voltage of the diode corresponds to a voltage difference between the first power source voltage and the feedback voltage when the first power source voltage is lower by a predetermined level than a breakdown voltage of the first and second switches.

15. The display device of claim 14, wherein, when the voltage difference between the first power source voltage and the feedback voltage reaches the threshold voltage of the diode, the feedback terminal is coupled to the first power source voltage output terminal through the diode.

16. The display device of claim 13, wherein the power controller further includes a first differential amplifier including a first input terminal to which the feedback voltage is input, a second input terminal to which a first reference voltage is input, and an output terminal outputting an over-voltage protection signal that corresponds to a voltage difference between the feedback voltage and the first reference voltage.

17. The display device of claim 16, wherein the power controller further includes a third switch coupled between the first switch and the first power source voltage output terminal and controls turning on and off of the third switch according to the over-voltage protection signal.

18. The display device of claim 14, wherein the power controller further includes a first resistor and a second resistor coupled in series between the feedback terminal and a ground and dividing a voltage that corresponds to a voltage difference between the feedback voltage and a ground voltage.

19. The display device of claim 18, wherein the power controller further includes a second differential amplifier including a first input terminal to which a voltage divided between the first resistor and the second resistor is input, a second input terminal to which a second reference voltage is input, and an output terminal outputting a voltage error signal that corresponds to a voltage difference between the divided voltage and the second reference voltage.

20. The display device of claim 19, wherein the power controller further includes a third differential amplifier including a first input terminal to which a first pulse width control signal is input, a second input terminal to which the voltage error signal is input, and an output terminal outputting a second pulse width control signal that corresponds to a voltage difference between the first pulse width control signal and the voltage error signal.

21. The display device of claim 20, wherein the power controller controls duties of the first and second switches according to the second pulse width control signal.

22. The display device of claim 13, wherein the power controller further includes a first capacitor including:

a first electrode coupled to the first power source voltage output terminal, and

a second electrode coupled to a ground.

23. The display device of claim 13, wherein the power controller further includes a second capacitor including:

a first electrode coupled to a second power source voltage terminal having the second power source voltage, and

a second electrode coupled to a ground.