Data driving device, a display driving device, and a display driving method
In the embodiment, the location of the defective pixel can be determined by measuring the operating current of each LED of the pixel, and the sub-LED can be driven in response to the location information of the defective pixel, thereby implementing normal LED operation even in a pixel defect situation.
1 . A data driving device, comprising:
a first sensing line electrically connected to a pixel circuit on a panel to receive an operating current of the pixel circuit;
a second sensing line electrically connected to the panel to receive a crack test signal;
a multiplexer connected to the first sensing line and the second sensing line to select and output one of the operating current which is received through the first sensing line at a first time section and the crack test signal which is received through the second sensing line at a second time section;
an analog-to-digital converter connected to the multiplexer and configured to convert the operating current into pixel current data or convert the crack test signal into crack test data; and
a demultiplexer connected to the analog-to-digital converter to output the pixel current data to a defective pixel detection circuit at the first time section and output the crack test data to a crack detection circuit at the second time section,
wherein the pixel circuit includes a first LED and a second LED,
wherein the data driving device is configured to determine a defective pixel and obtain defective pixel location information based on the operating current received through the first sensing line at the first time section, and
wherein when the defective pixel is determined, the data driving device is further configured to turn off the first LED and turn on the second LED before the second time section.
2 . The data driving device of claim 1 , wherein the data driving device is configured to supply a first driving voltage and a second driving voltage to selectively emit light in the first LED or the second LED included in the pixel circuit.
3 . The data driving device of claim 1 , wherein the data driving device is configured to scan a plurality of pixel circuits arranged on the panel line by line and detect the location of a defective pixel by sensing an output current of a corresponding pixel circuit.
4 . The data driving device of claim 1 ,
wherein the second sensing line is a signal line separated from a line of a driving voltage.
5 . The data driving device of claim 1 , wherein
when the operating current of the pixel circuit which is obtained through the first sensing line and which is associated with the first LED is out of a reference range, the data driving device is configured to determine that the first LED of the pixel circuit is defective, does not supply a driving current to the first LED, and supply the driving current to the second LED.
6 . The data driving device of claim 1 , wherein
the pixel circuit comprises:
a first path circuit comprising a first transistor and a second transistor disposed between a line of a first driving voltage and a line of a second driving voltage; and
a second path circuit comprising a third transistor, a fourth transistor, the first LED, a fifth transistor, a sixth transistor, and the second LED,
the third transistor, the fourth transistor, and the first LED are disposed between the line of the first driving voltage and the line of the second driving voltage,
the fifth transistor, the sixth transistor, and the second LED are disposed in parallel with the third transistor, the fourth transistor, and the first LED, and
the pixel circuit is configured to selectively emit light in one of the first LED and the second LED.
7 . The data driving device of claim 1 , wherein
the multiplexer is electrically connected to an input of the analog-to-digital converter,
the multiplexer is configured to receive the operating current and the crack test signal via the first and second sensing lines,
the multiplexer is configured to select one of the operating current and the crack test signal and output the selected one of the operating current and the crack test signal to the input of the analog-to-digital converter at the first time section via a single line connected between the multiplexer and the analog-to-digital converter, and
the multiplexer is configured to select another one of the operating current and the crack test signal and output the selected another one of the operating current and the crack test signal to the input of the analog-to-digital converter at the second time section that is different from the first time section via the single line connected between the multiplexer and the analog-to-digital converter.
8 . The data driving device of claim 7 , wherein
the demultiplexer is electrically connected to an output of the analog-to-digital converter,
the demultiplexer is configured to receive, from the analog-to-digital converter, the pixel current data and the crack test data at different time sections via a single line connected between the analog-to-digital converter and the demultiplexer,
the demultiplexer is electrically connected to a defective pixel detection circuit and a chip crack detection circuit,
the demultiplexer is configured to select the defective pixel detection circuit from among the defective pixel detection circuit and the chip crack detection circuit and output the pixel current data to the selected defective pixel detection circuit, and
the demultiplexer is configured to select the chip crack detection circuit from among the defective pixel detection circuit and the chip crack detection circuit and output the crack test data to the selected chip crack detection circuit.
9 . A method performed by a data driving device, the method comprising:
receiving an operating current of a pixel circuit on a panel via a first sensing line electrically connected to the pixel circuit;
receiving a crack test signal via a second sensing line electrically connected to the panel;
using a multiplexer connected to the first sensing line and the second sensing line, selecting and outputting one of the operating current which is received through the first sensing line at a first time section and the crack test signal which is received through the second sensing line at a second time section;
using an analog-to-digital converter connected to the multiplexer, converting the operating current into pixel current data or converting the crack test signal into crack test data; and
using a demultiplexer connected to the analog-to-digital converter, outputting the pixel current data to a defective pixel detection circuit at the first time section and outputting the crack test data to a crack detection circuit at the second time section,
wherein the pixel circuit includes a first LED and a second LED,
wherein the method further comprises:
determining a defective pixel and obtain defective pixel location information based on the operating current received through the first sensing line at the first time section, and
when the defective pixel is determined, turning off the first LED and turning on the second LED before the second time section.
10 . The method of claim 9 , wherein
the multiplexer is electrically connected to an input of the analog-to-digital converter, and
the method comprises
receiving at the multiplexer the operating current and the crack test signal via the first and second sensing lines;
selecting at the multiplexer one of the operating current and the crack test signal;
outputting from the multiplexer the selected one of the operating current and the crack test signal to the input of the analog-to-digital converter at the first time section via a single line connected between the multiplexer and the analog-to-digital converter;
selecting at the multiplexer another one of the operating current and the crack test signal; and
outputting from the multiplexer the selected another one of the operating current and the crack test signal to the input of the analog-to-digital converter at the second time section that is different from the first time section via the single line connected between the multiplexer and the analog-to-digital converter.
11 . The method of claim 10 , wherein
the demultiplexer is electrically connected to an output of the analog-to-digital converter,
the demultiplexer is electrically connected to a defective pixel detection circuit and a chip crack detection circuit, and
the method comprises:
receiving at the demultiplexer, from the analog-to-digital converter, the pixel current data and the crack test data at different time sections via a single line connected between the analog-to-digital converter and the demultiplexer;
selecting at the demultiplexer the defective pixel detection circuit from among the defective pixel detection circuit and the chip crack detection circuit;
outputting from the demultiplexer the pixel current data to the selected defective pixel detection circuit;
selecting at the demultiplexer the chip crack detection circuit from among the defective pixel detection circuit and the chip crack detection circuit;
outputting from the demultiplexer the crack test data to the selected chip crack detection circuit.