Source driver and display device having the same
A source driver includes a plurality of output buffers configured to output data signals respectively corresponding to a plurality of data lines, and an output controller configured to control a timing at which each of the data signals corresponding to second image data is transferred from the output buffers to the data lines based on a difference between first image data and the second image data.
1. A source driver comprising:
a plurality of output buffers configured to output data signals respectively corresponding to a plurality of data lines; and
an output controller configured to control a timing at which one of the data signals corresponding to second image data begins to be transferred from one of the output buffers to one of the data lines based on a difference between first image data and the second image data, the first image data corresponding to a data signal supplied to a first pixel in a first pixel row, and the second image data corresponding to a data signal supplied to a second pixel included in a second pixel row that is different from the first pixel row, the first and second pixels being in a same pixel column.
2. The source driver of claim 1 , wherein the first image data corresponds to a data signal supplied to a pixel in a (k−1)th pixel row, and wherein the second image data corresponds to a data signal supplied to a pixel in a kth pixel row, k being a natural number that is greater than 1.
3. A source driver comprising:
a plurality of output buffers configured to output data signals respectively corresponding to a plurality of data lines; and
an output controller configured to control a timing at which each of the data signals corresponding to second image data is transferred from the output buffers to the data lines based on a difference between first image data and the second image data, the first image data corresponding to a data signal supplied to a first pixel in a first pixel row, and the second image data corresponding to a data signal supplied to a second pixel included in a second pixel row that is different from the first pixel row,
wherein the output controller comprises:
a delay determiner configured to output an output delay signal based on results obtained by comparing the first image data and the second image data with a threshold reference; and
a delay switch coupled between an output terminal of one of the output buffers and one of the data lines, and configured to be turned off in response to the output delay signal.
4. The source driver of claim 3 , wherein, when a grayscale difference between the first image data and the second image data is less than a reference difference, the delay determiner is configured to output the output delay signal.
5. The source driver of claim 4 , wherein, when the grayscale difference between the first image data and the second image data is greater than or equal to the reference difference, the delay switch is configured to maintain a turn-on state.
6. The source driver of claim 3 , wherein a period in which the delay switch is turned off is shorter than one horizontal period.
7. The source driver of claim 3 , wherein, when the delay switch is turned off, an output buffer corresponding to the delay switch is configured to have an electrically high-impedance state from a data line corresponding thereto.
8. The source driver of claim 3 , wherein, when the first image data and the second image data are equal to or greater than a first reference grayscale, the delay determiner is configured to output the output delay signal.
9. The source driver of claim 8 , wherein, when the first image data and the second image data are equal to or less than a second reference grayscale, the delay determiner is configured to output the output delay signal, and
wherein the second reference grayscale is greater than the first reference grayscale.
10. The source driver of claim 9 , wherein the delay switch is configured to be turned off during a delay period in response to the output delay signal.
11. The source driver of claim 9 , wherein, when one of the first image data and the second image data is less than the first reference grayscale while the other of the first image data and the second image data is greater than the second reference grayscale, the delay switch is configured to maintain a turn-on state.
12. The source driver of claim 3 , wherein the output controller further comprises a pre-charge switch coupled between the one of the data lines and a power source, and is configured to be turned on in response to the output delay signal.
13. The source driver of claim 12 , wherein, during a delay period in which the delay switch is turned off, a voltage of the power source is supplied to a data line corresponding to the pre-charge switch among the data lines.
14. A display device comprising:
a display panel comprising a plurality of pixels;
a scan driver configured to supply a scan signal to the pixels in units of pixel rows; and
a source driver configured to supply data signals to the pixels in response to the scan signal, and comprising:
a plurality of output buffers configured to output the data signals to a plurality of data lines, respectively; and
an output controller configured to control a timing at which a current data corresponding to current image data begins to be transferred from one of the output buffers to one of the data lines based on a difference between previous image data and the current image data, the previous image data corresponding to a previous data signal supplied to a first pixel in a first pixel row, and the current image data corresponding to a current data signal supplied to a second pixel included in a second pixel row that is different from the first pixel row, the first and second pixels being in a same pixel column,
wherein the output controller comprises:
a delay determiner configured to output an output delay signal based on a result obtained by comparing a grayscale difference between the previous image data and the current image data with a reference difference; and
a delay switch coupled between an output terminal of one of the output buffers and one of the data lines, and configured to be turned off in response to the output delay signal.
15. The display device of claim 14 , wherein the previous image data corresponds to a data signal supplied to a pixel in a (k−1)th pixel row, and wherein the current image data corresponds to a data signal supplied to a pixel in a kth pixel row, k being a natural number that is greater than 1.
16. The display device of claim 14 , wherein, when the grayscale difference is less than the reference difference, the delay determiner is configured to output the output delay signal.
17. The display device of claim 14 , wherein, when the grayscale difference is greater than or equal to the reference difference, the delay switch is configured to maintain a turn-on state.
18. The display device of claim 14 , wherein, when the delay switch is turned off, an output buffer corresponding to the delay switch is configured to have an electrically high-impedance from a data line corresponding thereto.