Current sample/hold circuit and display device using the same, and display panel and driving method thereof

A display device comprising:

• a display unit including a plurality of data lines for transmitting data currents, a plurality of scan lines for transmitting scan signals, and a plurality of pixel areas defined by the data lines and the scan lines;
• a first shift register for generating a plurality of second signals by sequentially delaying a first signal for a period;
• a latch for latching a plurality of grayscale data in synchronization with the second signals;
• a grayscale current generator for receiving the plurality of grayscale data and for outputting the data currents corresponding to the grayscale data;
• and
• an output unit for applying the data currents output from the grayscale current generator to the plurality of data lines,
• wherein the grayscale current generator comprises a bias current generator for generating a plurality of bias currents and a plurality of digital/analog (D/A) converters for using the plurality of bias currents to output the data currents corresponding to the grayscale data, the plurality of bias currents being different from each other, and
• wherein each of the D/A converters comprises a plurality of current sample/hold circuits for storing first voltages corresponding to the bias currents in at least two capacitors, and for outputting currents corresponding to the first voltages in response to the grayscale data.

A grayscale current generator for generating a grayscale current based on input grayscale data, comprising a plurality of digital/analog (D/A) converters,

• wherein each of the plurality of D/A converters comprises:
• a first current generator for generating a plurality of first currents, the plurality of first currents being different from each other;
• and
• a plurality of current sample/hold circuits for respectively storing first voltages corresponding to the first currents in at least two capacitors, and respectively outputting second currents corresponding to the first voltages in response to the grayscale data, and
• wherein the D/A converters gather second currents output from the plurality of current sample/hold circuits and output a sum of the second currents as the grayscale current.

A current sample/hold circuit for sampling and holding a first current, comprising:

• first and second transistors, each having first, second and third electrodes, the first and second transistors being cascade-connected to a power source, and diode-connected in response to a first control signal;
• first and second capacitors respectively coupled between the first electrodes of the first and second transistors and the power source;
• a first switch for applying the first current to the first and second transistors in response to a second control signal;
• and
• a second switch coupled to the third electrode of the second transistor, and for holding a current flowing to the second transistor in response to a third control signal.

A driving method of a display panel having a plurality of pixels for displaying an image corresponding to data currents, the driving method comprising:

• generating a plurality of first currents that are different from each other;
• sampling the first currents and respectively storing a plurality of first voltages corresponding to the first currents in at least two capacitors;
• respectively outputting a plurality of second currents corresponding to the plurality of first voltages in response to grayscale data;
• and
• adding the plurality of second currents and outputting a sum of the second currents as at least one of the data currents.