Data driver for electrophoretic display
AssigneeNovatek Microelectronics Corp.
InventorsShih-Hung Huang, Feng-Ting Pai
Life of this patent
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Abstract
A data driver for an electrophoretic display (EPD) includes multiple driver sub-circuits. Each of the driver sub-circuits includes first and second latches, first and second capacitors, a multiplexer and a comparator. The first and second latches respectively provide updated latch image data and current latch image data in response to original image data. When the updated and current latch image data correspond to different levels, the comparator controls the multiplexer in a first period to selectively couple one of the first and second capacitors to a driver end, so as to recycle charges at pixels, and controls the multiplexer in a second period to selectively couple the other of the first and second capacitors to the driver end to pre-charge the pixels with the charges.
Claims12
A data driver for an electrophoretic display (EPD), comprising a plurality of driver sub-circuits, each of the driver sub-circuits driving a pixel column of the EPD in a driving period via a driver end;
- wherein each of the driver sub-circuits comprises:
- an output node;
- a first latch and a second latch, for respectively storing updated latch image data and current latch image data in response to original image data, the second latch further providing the current latch image data to the output node, the updated latch image data and the current latch image data each selectively corresponding individually to one of a positive reference level, a negative reference level and a ground reference level;
- a multiplexer, coupled to a first capacitor, a second capacitor, the output node and the driver end;
- and
- a comparator, dividing the driving period into a first period, a second period and a third period, wherein when the updated latch image data and the current latch image data selectively correspond to different levels, the comparator controls the multiplexer to selectively couple one of the first and second capacitors to the driver end in the first period to recycle charges at the pixel column into the coupled one of the first and second capacitors, and to selectively couple said one of the first and second capacitors to the driver end in the second period to pre-charge or pre-discharge the pixel column with the recycled charges in the coupled one of the first and second capacitors,
- wherein when the current latch image data correspond to the positive reference level, and the updated and current latch image data correspond to different levels, the comparator controls the multiplexer to couple the first capacitor to the driver end in the first period to recycle positive charges at the pixel column to the first capacitor.
Dependencies are inferred from the claim text.