Selective display driving method and apparatus based on the characteristics of light-emitting diode
Display driving method and device capable of selecting driving pulse types. The display device includes a plurality of pixels, each of the plurality of pixels including a luminous element and a pixel circuit connected to the luminous element; and a data driver configured to provide image data and luminance data of the pixels to the pixel circuit, wherein the image data comprises multi-bit values including a Most Significant Bit (MSB) and a Least Significant Bit (LSB); and a processor configured to generate a Pulse Width Modulation (PWM) signal based on the multi-bit values when the luminance data is greater than a threshold value, and control light-emission and non-emission of the luminous element through the PWM signal, and drive the LSB using an impulse signal when the luminance data is less than the threshold value.
1 . A display device comprising:
a plurality of pixels, each of the plurality of pixels including a luminous element and a pixel circuit connected to the luminous element; and
a data driver configured to provide image data and luminance data of the pixels to the pixel circuit, wherein the image data is represented as multi-bit values consisting of a Most Significant Bit (MSB) to a Least Significant Bit (LSB); and
a processor configured to
generate a Pulse Width Modulation (PWM) signal based on the multi-bit values when the luminance data is greater than a threshold value, and control light-emission and non-emission of the luminous element through the PWM signal, and
drive the LSB using an impulse signal when the luminance data is less than the threshold value.
2 . The display device of claim 1 , wherein, if the luminance data is less than the threshold value, the pixel circuit is configured to drive at least one upper bit of the multi-bit values based on the PWM signal and at least one lower bit of the multi-bit values based on the impulse signal.
3 . The display device of claim 1 , wherein the number of bits of the multi-bit values, the number of bits being driven based on impulse signals, is determined based on an on-duty ratio corresponding to a light emission period within one frame.
4 . The display device of claim 1 , wherein the threshold value is determined based on at least one of a display driving frequency, an on-duty ratio, or the number of grayscale bits.
5 . The display device of claim 1 , wherein the threshold value is determined based on a grayscale-luminance linearity of each of the luminance elements.
6 . A display driving method comprising:
receiving image data and luminance data on a display pixel from a processor;
retrieving a luminance value from the luminance data;
comparing the luminance value to a threshold value; and
controlling light-emission and non-emission of a luminous element through a PWM signal and an impulse signal when the luminance data is less than the threshold value.
7 . The method of claim 6 , wherein the image data is represented as multi-bit values consisting of MSB (Most Significant Bit) to LSB (Least Significant Bit), and
if the luminance data is less than the threshold value, driving upper bits of the multi-bit values based on the PWM signal and driving lower bits of the multi-bit values based on the impulse signal.
8 . A display driving device capable of selecting driving pulse types, the display driving device comprising:
a detector configured to receive and detect luminance data from image data and luminance data on a display pixel including a light emitting diode (LED) from a data driver;
a processor configured to select
a pulse width modulation (PWM) signal or an impulse signal based on the luminance data and, when the luminance data is less than a preset reference value,
generate a scan signal that includes the impulse signal, and
output the scan signal to a row terminal of the display pixel; and
a pixel driving circuit disposed in the display pixel and configured to drive the LED based on the image data and the scan signal.
9 . The selective display driving device of claim 8 , wherein the scan signal includes the PWM signal corresponding to an upper bit of the image data and the impulse signal corresponding to a lower bit of the image data.
10 . The display driving device of claim 9 , wherein a composition ratio of the PWM signal and the impulse signal is adjusted in response to an on-duty ratio of one frame.
11 . The display driving device of claim 10 , wherein a proportion of the impulse signal in the scan signal increases according to a decrease in the on-duty ratio.
12 . A pixel driving circuit of a display pixel, the pixel driving circuit comprising:
a luminance memory configured to receive luminance data for the display pixel and to store the luminance data;
a memory configured to store bit values of image data;
a controller configured to generate
a first control signal based on the bit values and a pulse width modulation (PWM) signal, and
generate a second control signal based on the bit values and an impulse signal;
a selector configured to select the first control signal or the second control signal based on the luminance data; and
a pixel driver configured to deliver, to an LED, or block driving current based on an output signal of the selector.
13 . The pixel driving circuit of claim 12 , wherein the selector is configured to select the first control signal if the luminance data is greater than or equal to a preset reference value and to select the second control signal if the luminance data is less than the preset reference value.
14 . The pixel driving circuit of claim 12 , wherein the selector is configured to select the first control signal in a section corresponding to an upper bit of the bit values and to select the second control signal in a section corresponding to a lower bit of the bit values if the luminance data is less than a preset reference value.
15 . The pixel driving circuit of claim 12 , wherein the selector is configured to identify each of a plurality of subpixels and to select the first control signal or the second control signal.