Organic light emitting display device

Patent metadata

Field	Value
Publication number	US-9392653-B2
Application number	US-201213591538-A
Country	US
Kind code	B2
Filing date	Aug 22, 2012
Priority date	Nov 3, 2011
Publication date	Jul 12, 2016
Grant date	Jul 12, 2016

Abstract

An organic light emitting display device includes a display panel including an organic light emitting diode, a power supply including a DC-DC converter that generates a driving voltage for the organic light emitting diode and that provides the driving voltage to the display panel, the DC-DC converter including an inductor and a switch, and an over-current prevention unit that blocks supply of the driving voltage when a value of a current flowing through the inductor is greater than a reference value.

First claim

What is claimed is:

1. An organic light emitting display device comprising:
a display panel comprising an organic light emitting diode;
a power supply comprising a DC-DC converter configured to generate a driving voltage for the organic light emitting diode, and configured to provide the driving voltage to the display panel, the DC-DC converter comprising an inductor and a switch; and
an over-current prevention unit comprising:
a comparison unit configured to compare a value of a current flowing through the inductor with a reference value, and configured to generate a comparison result;
a detector coupled to an output terminal of the inductor, and configured to detect the current flowing through the inductor; and
a counter coupled to an output of the comparison unit, and configured to count a voltage block signal that is output from the comparison unit when the value of the current flowing through the inductor is greater than the reference value; and
a block unit configured to block supply of the driving voltage either based on the comparison result or when a counted number of the voltage block signal is equal to a reference number.

2. The device of claim 1 , wherein the comparison unit corresponds to a comparator that is configured to output a signal having a logic high level or a logic low level based on the comparison result.

3. The device of claim 1 , further comprising a controller configured to provide a power control signal to the power supply, the power control signal for allowing the supply of the driving voltage,
wherein the block unit is further configured to block the power control signal based on the comparison result, the block unit being located between the controller and the power supply.

4. The device of claim 1 , wherein the block unit is further configured to shut-off a supply-line of the driving voltage based on the comparison result, the block unit being located between the power supply and the display panel.

5. The device of claim 1 , wherein the over-current prevention unit further comprises a reference set unit configured to set the reference value.

6. The device of claim 5 , wherein the reference set unit comprises:
a look-up table for storing a plurality of reference values that are suitable for a plurality of display panels, sizes of the display panels being different from one another; and
a selection unit configured to select and output one of the reference values.

7. The device of claim 6 , wherein the selection unit is further configured to select one of the reference values based on a selection signal that is provided from outside.

8. The device of claim 1 , wherein the counter is further configured to provide the voltage block signal to the block unit when the counted number is equal to the reference number, and wherein the counter is located between the comparison unit and the block unit.

9. The device of claim 8 , wherein the counter is further configured to receive a count clock signal from outside, the count clock signal being used for controlling a count cycle.

10. The device of claim 1 , further comprising:
a scan driver configured to provide a scan signal to the display panel;
a data driver configured to provide a data voltage to the display panel; and
a controller configured to provide a scan control signal to the scan driver, to provide a data control signal and a data signal to the data driver, and to provide a power control signal to the power supply.

11. An organic light emitting display device comprising:
a display panel comprising an organic light emitting diode;
a power supply comprising a first DC-DC converter configured to generate a first driving voltage for the organic light emitting diode and to provide the first driving voltage to the display panel, and a second DC-DC converter configured to generate a second driving voltage for the organic light emitting diode and to provide the second driving voltage to the display panel, the first DC-DC converter comprising a first inductor and a first switch, the second DC-DC converter comprising a second inductor and a second switch, the first driving voltage being different from the second driving voltage; and
an over-current prevention unit configured to compare a value of a current flowing through the first inductor with a first reference value, to compare a value of a current flowing through the second inductor with a second reference value, and to block supplies of the first and second driving voltages when the value of the current flowing through the first inductor is greater than the first reference value, or when the value of the current flowing through the second inductor is greater than the second reference value,
wherein the over-current prevention unit comprises a first detector directly coupled to an output terminal of the first inductor.

12. The device of claim 11 , wherein the first detector is configured to detect current flowing through the first inductor, and the over-current prevention unit further comprises:
a second detector configured to detect the current flowing through the second inductor;
a first comparison unit configured to compare the value of the current flowing through the first inductor with the first reference value;
a second comparison unit configured to compare the value of the current flowing through the second inductor with the second reference value; and
a block unit configured to block supply of the first and second driving voltages based on comparison results generated by the first and second comparison units.

13. An organic light emitting display device comprising:
a display panel comprising an organic light emitting diode;
a power supply comprising a first DC-DC converter configured to generate a first driving voltage for the organic light emitting diode and to provide the first driving voltage to the display panel, and a second DC-DC converter configured to generate a second driving voltage for the organic light emitting diode and to provide the second driving voltage to the display panel, the first DC-DC converter comprising a first inductor and a first switch, the second DC-DC converter comprising a second inductor and a second switch, the first driving voltage being different from the second driving voltage; and
an over-current prevention unit configured to block supplies of the first and second driving voltages when a value of a current flowing through the first inductor is greater than a first reference value, or when a value of a current flowing through the second inductor is greater than a second reference value, wherein the over-current prevention unit comprises:
a first detector configured to detect the current flowing through the first inductor;
a second detector configured to detect the current flowing through the second inductor;
a first comparison unit configured to compare a value of the current flowing through the first inductor with the first reference value;
a second comparison unit configured to compare a value of the current flowing through the second inductor with the second reference value;
a block unit configured to block supply of the first and second driving voltages based on comparison results generated by the first and second comparison units; and
an OR-gate configured to perform an OR operation between the comparison result generated by the first comparison unit and the comparison result generated by the second comparison unit, the OR-gate being located between the first comparison unit and the second comparison unit.

14. The device of claim 13 , wherein the over-current prevention unit further comprises:
a counter configured to count a volt

Assignees

• Lee Hee-Chul
• Kim Min-Weun
• Samsung Display Co Ltd

Inventors

• Lee Hee-Chul
• Kim Min-Weun

Classifications

• G06F3/038

  Control and interface arrangements therefor, e.g. drivers or device-embedded control circuitry · CPC title

• H05B33/0815 Primary

  Electricity · mapped topic

• Y02B20/341

  Cross-Sectional Technologies · mapped topic

• H05B45/38

  using boost topology · CPC title

• H05B45/3725 Primary

  Switched mode power supply [SMPS] · CPC title