Apparatus for driving display panel using cascaded integrated circuits
A display driving device includes two or more integrated circuits configured to receive image data from a device through a main communication line, wherein the two or more integrated circuits are connected in a cascade form for subsidiary communication, a first integrated circuit disposed at an end of the cascade transmits a first subsidiary communication signal to the device through the subsidiary communication, and a second integrated circuit disposed at a beginning of the cascade receives a feedback signal for the first subsidiary communication signal from the device, thereby providing a technique of simultaneously initializing all data driving devices even if an error occurs in one of a plurality of data driving devices and easily synchronizing operation modes of the data driving devices and a data processing device.
1 . A display driving device comprising two or more integrated circuits configured to receive image data from a device through a main communication line,
wherein the two or more integrated circuits are connected in a cascade form for subsidiary communication, a first integrated circuit disposed at an end of the cascade transmits a first subsidiary communication signal to the device through the subsidiary communication, and a second integrated circuit disposed at a beginning of the cascade receives a feedback signal for the first subsidiary communication signal from the device,
wherein a subsidiary communication output terminal of the first integrated circuit is connected to the device, and a subsidiary communication input terminal of the second integrated circuit is connected to the device.
2 . The display driving device of claim 1 , wherein each integrated circuit performs the subsidiary communication by combining an input signal received from the subsidiary communication input terminal and a state signal indicating a communication state of the main communication line and outputting the combined signal to the subsidiary communication output terminal.
3 . The display driving device of claim 2 , wherein each integrated circuit outputs a subsidiary communication signal obtained by combining the input signal and the state signal through an AND operation to the subsidiary communication output terminal.
4 . The display driving device of claim 2 , wherein each integrated circuit determines that an abnormality has occurred in at least one of the two or more integrated circuits when the input signal or the state signal has a low level voltage.
5 . The display driving device of claim 2 , wherein each integrated circuit switches to a mode of retraining a communication clock signal of the main communication line when the input signal or the state signal has a low level voltage.
6 . The display driving device of claim 1 , wherein the device generates the feedback signal at a low level voltage and transmits the feedback signal when the first subsidiary communication signal has a low level voltage.
7 . The display driving device of claim 1 , wherein the device transmits a reset signal through the feedback signal, and the two or more integrated circuits receive the reset signal through the subsidiary communication.
8 . The display driving device of claim 7 , wherein each integrated circuit decreases a data rate of main communication through the main communication line after the reset signal is received.
9 . The display driving device of claim 8 , wherein each integrated circuit receives the image data in a high-speed mode and receives configuration data for the high-speed mode in a low-speed mode having a lower data rate than the high-speed mode.
10 . A display driving device comprising:
a main communication circuit configured to transmit image data to two or more integrated circuits through main communication lines; and
a subsidiary communication circuit configured to receive a first subsidiary communication signal from a first integrated circuit disposed at an end of a cascade among the two or more integrated circuits connected in a cascade form for subsidiary communication and to transmit a feedback signal for the first subsidiary communication signal to a second integrated circuit disposed at a beginning of the cascade,
wherein a subsidiary communication output terminal of the first integrated circuit is connected to the subsidiary communication circuit, and a subsidiary communication input terminal of the second integrated circuit is connected to the subsidiary communication circuit.
11 . The display driving device of claim 10 , wherein the main communication circuit transmits a clock training signal for retraining a communication clock signal of the image data to the main communication lines when the first subsidiary communication signal indicates an abnormal state of at least one of the main communication lines.
12 . The display driving device of claim 10 , wherein the main communication circuit transmits the image data in a high-speed mode and transmits configuration data for the high-speed mode to the main communication lines in a low-speed mode having a lower data rate than the high-speed mode.
13 . The display driving device of claim 12 , wherein the main communication circuit switches from the high-speed mode to the low-speed mode when the first subsidiary communication signal indicates an abnormal state of at least one of the main communication lines.
14 . The display driving device of claim 10 , wherein the subsidiary communication circuit transmits a reset signal through the feedback signal to reset the two or more integrated circuits.
15 . The display driving device of claim 10 , wherein the subsidiary communication circuit generates the feedback signal at a low level voltage and transmits the feedback signal when the first subsidiary communication signal has a low level voltage.
16 . The display driving device of claim 15 , wherein the main communication circuit transmits a clock training signal for retraining a communication clock signal of the image data to the main communication lines when the first subsidiary communication signal has a low level voltage.
17 . A display driving device comprising:
two or more integrated circuits connected in a cascade form for subsidiary communication; and
a device configured to transmit image data to the two or more integrated circuits through main communication lines, to receive a first subsidiary communication signal from a first integrated circuit disposed at an end of the cascade, and to transmit a feedback signal for the first subsidiary communication signal to a second integrated circuit disposed at a beginning of the cascade,
wherein a subsidiary communication output terminal of the first integrated circuit is connected to the device, and a subsidiary communication input terminal of the second integrated circuit is connected to the device.
18 . The display driving device of claim 17 , wherein each integrated circuit performs the subsidiary communication by combining an input signal received from the subsidiary communication input terminal and a state signal indicating a communication state of each main communication line and outputting the combined signal to the subsidiary communication output terminal.
19 . The display driving device of claim 18 , wherein the subsidiary communication output terminal of the first integrated circuit is connected to the device, and the subsidiary communication input terminal of the second integrated circuit is connected to the device.