Display device having a short circuit protection part to output a shutdown signal
Disclosed is a display device which includes a voltage generator including a first converter that generates a first voltage using an input voltage and is shut down in response to a shutdown signal and a short circuit protection part including a first short circuit protection part that compares an output voltage of an output terminal of the first converter with a first reference voltage and outputs the shutdown signal. The first converter pre-charges the output voltage to a predetermined voltage level during a first period, maintains a level of the output voltage during a second period subsequent to the first period, and boosts and outputs the output voltage as the first voltage during a third period subsequent to the second period. The first short circuit protection part outputs the shutdown signal when the output voltage in the second period has a level lower than that of the first reference voltage.
1. A display device, comprising:
a voltage generator including a first converter configured to generate a first voltage using an input voltage and configured to be shut down in response to a shutdown signal;
a display panel including a pixel for receiving the first voltage; and
a short circuit protection part including a first short circuit protection part configured to compare an output voltage of an output terminal of the first converter with a first reference voltage and output the shutdown signal depending on the compared result,
wherein the first converter pre-charges the output voltage to a predetermined voltage level during a first period, maintains a level of the output voltage during a second period subsequent to the first period, and boosts and outputs the output voltage as the first voltage during a third period subsequent to the second period, and
wherein the first short circuit protection part outputs the shutdown signal when the output voltage in the second period has a level lower than that of the first reference voltage.
2. The display device of claim 1 , wherein the first reference voltage has a level lower than that of the input voltage.
3. The display device of claim 1 , wherein the first reference voltage is about 80% to about 90% of the input voltage.
4. The display device of claim 1 , wherein the first reference voltage is a value obtained by subtracting 500 mV from the input voltage.
5. The display device of claim 1 , wherein the first short circuit protection part outputs the shutdown signal when the output voltage maintains a level lower than that of the first reference voltage during a first holding period in the second period.
6. The display device of claim 1 , wherein the first short circuit protection part includes:
a first comparator configured to compare the output voltage with the first reference voltage and output a first comparison signal when the output voltage has a level lower than that of the first reference voltage.
7. The display device of claim 6 , wherein the first comparison signal is the shutdown signal.
8. The display device of claim 6 , wherein the first short circuit protection part further includes:
a first short circuit determination part configured to output the shutdown signal as the first comparison signal when the first comparison signal is maintained during a first holding period.
9. The display device of claim 8 , wherein the first holding period is shorter than the second period.
10. The display device of claim 1 , wherein the voltage generator further includes:
a second converter configured to generate a second voltage having a level lower than that of the first voltage using the input voltage, and
wherein the pixel is driven by the first voltage and the second voltage to display an image in an image display period.
11. The display device of claim 10 , wherein the short circuit protection part further includes:
a second short circuit protection part configured to compare the output voltage with a second reference voltage during the image display period and output the shutdown signal when the output voltage has a level lower than that of the second reference voltage; and
a third short circuit protection part configured to compare the output voltage with a third reference voltage during the image display period and output the shutdown signal when the output voltage has a level lower than that of the third reference voltage, and
wherein the third reference voltage and the second reference voltage have different levels.
12. The display device of claim 11 , wherein the third reference voltage has a level higher than that of the second reference voltage.
13. The display device of claim 11 , wherein the second reference voltage is about 50% of a normal output voltage which is an initial level of the boosted output voltage.
14. The display device of claim 13 , wherein the third reference voltage is about 85% of the normal output voltage.
15. The display device of claim 11 , wherein the second short circuit protection part outputs the shutdown signal when the output voltage has the level lower than that of the second reference voltage during a second holding period.
16. The display device of claim 15 , wherein the third short circuit protection part outputs the shutdown signal when the output voltage has the level lower than that of the third reference voltage during a third holding period, and
wherein the third holding period is longer than the second holding period.
17. The display device of claim 11 , wherein the second short circuit protection part includes:
a second comparator configured to compare the output voltage with the second reference voltage and output a second comparison signal when the output voltage has the level lower than that of the second reference voltage; and
a second short circuit determination part configured to output the shutdown signal as the second comparison signal when the second comparison signal is maintained during a second holding period.
18. The display device of claim 11 , wherein the third short circuit protection part includes:
a third comparator configured to compare the output voltage with the third reference voltage and output a third comparison signal when the output voltage has the level lower than that of the third reference voltage; and
a third short circuit determination part configured to output the shutdown signal as the third comparison signal when the third comparison signal is maintained during a third holding period.
19. A display device, comprising:
a voltage generator including a first converter configured to generate a first voltage using an input voltage and configured to be shut down in response to a shutdown signal;
a display panel including a pixel for receiving the first voltage; and
a short circuit protection part including a first short circuit protection part configured to compare an output voltage of an output terminal of the first converter outputting the first voltage with a first reference voltage and output the shutdown signal depending on the compared result,
wherein the first converter pre-charges the output voltage to a predetermined voltage level during a first period, maintains a level of the output voltage during a second period subsequent to the first period, and boosts and outputs the output voltage as the first voltage during a third period subsequent to the second period, and
wherein the first short circuit protection part outputs the shutdown signal when the output voltage has a level lower than that of the first reference voltage and maintains the level lower than that of the first reference voltage during a first holding period in the second period.
20. The display device of claim 19 , wherein the first holding period is shorter than the second period.