Liquid crystal display device having balanced clock signal lines
View Patent ↗The present invention provides a liquid crystal display device which can effectively reduce electromagnetic radiation caused by clock signals or data signals. In a liquid crystal display device, a timing controller outputs a clock signal and a reverse clock signal. The clock signal and the reverse clock signal are transmitted to a clock signal line and a reverse clock signal line arranged in parallel to each other. The clock signal line is connected to normal terminals of data driver ICs, and the reverse clock signal line is connected to dummy terminals of the data driver ICs.
1. A liquid crystal display device comprising:
a liquid crystal display panel;
a plurality of data driver integrated circuits (ICs) for driving data lines of the liquid crystal display panel;
a first clock signal line for transmitting a first clock signal to the plurality of data driver ICs;
a second clock signal line which is equipped in parallel with the first signal line and transmits a second clock signal which is in reverse relation with the first clock signal;
a timing controller for outputting the first and second clock signals to the first and second clock signal lines respectively; and
load means for making the load capacitance of the second clock signal line equal to or substantially equal to the load capacitance of the first clock signal line.
2. The liquid crystal display device according to claim 1 , wherein the load means is constructed by equipping dummy terminals to the data driver ICs, and connecting the second clock signal line to the dummy terminals.
3. The liquid crystal display device according to claim 1 , wherein the load means is constructed by containing a capacitor in a terminating circuit.
4. The liquid crystal display device according to claim 3 , wherein the capacitor has the same capacitance value as the input capacitance of the first clock signal input terminals of the data driver ICs.
5. The liquid crystal display device according to claim 1 , wherein a data signal line for odd-number dots for transmitting data signals of odd-number dots and a data signal line for even-number dots for transmitting data signals of even-number dots are equipped, and the timing controller outputs the data signals of the odd-number dots and the data signals of the even-number dots every horizontal line while displacing the phase between the data signals of the odd-number and even-number dots by 180 degrees, and the data driver ICs input the first and second clock signals, latch the data signals of the odd-number dots with the first clock signal and latch the data signals of the even-number dots with the second clock signal.
6. The liquid crystal display device according to claim 5 , wherein a data signal of a dot is consisted of a plurality of bits, and
the timing controller has output pins for the data signals arranged so that the data signal of an odd-number dot of each bit of each color and the data signal of an even-number dot of the same bit are adjacent to each other.