Backlight control system and the backlight driver chip used therein

Abstract

This invention discloses a backlight control system and a backlight driver chip used therein. The backlight driver chip used in the backlight control system includes two bidirectional communication modules and a control module. The control module is configured to: set the two bidirectional communication modules to a signal output mode and output a detection signal through the communication connection port of each of the two bidirectional communication modules, the signal strength of which is a preset signal strength; detect the instantaneous signal strength at the communication connection port of each of the two bidirectional communication modules; designate one of the two bidirectional communication modules whose instantaneous signal strength is greater than the preset signal strength as the master communication module of the backlight driver chip, and designate the other bidirectional communication module as the slave communication module of the backlight driver chip.

Claims

1. A backlight driver chip used in a backlight control system, comprising two bidirectional communication modules and a control module, wherein, The control module is configured to: set the two bidirectional communication modules to signal output mode, and output a detection signal through the communication connection port of each of the two bidirectional communication modules, wherein the signal strength of the detection signal is a preset signal strength; detect the instantaneous signal strength at the communication connection port of each of the two bidirectional communication modules; and set one of the two bidirectional communication modules whose instantaneous signal strength is greater than the preset signal strength as the master communication module of the backlight driver chip, and set the other of the two bidirectional communication modules as the slave communication module of the backlight driver chip.

2. The backlight driver chip as described in claim 1, wherein, Each of the two bidirectional communication modules includes a signal input link and a signal output link connected in parallel between the communication connection ports of the control module and the bidirectional communication module. The bidirectional communication module is set to signal output mode when the signal output link is valid and to signal input mode when the signal output link is invalid.

3. The backlight driver chip as described in claim 2, wherein, The signal output link includes a signal output buffer and a signal limiting unit. The signal output buffer is used to generate the detection signal, and the signal limiting unit is used to limit the signal strength of the detection signal to the preset signal strength.

4. The backlight driver chip as described in claim 3, wherein, The signal limiting unit includes a switch and a limiting resistor connected in parallel between the output terminal of the signal output buffer and the communication connection port of the bidirectional communication module. The limiting resistor is used to limit the signal strength of the detected signal to the preset signal strength when the switch is in the open state.

5. The backlight driver chip as described in claim 4, wherein, The control module is further configured to control the switches in the two communication modules to change from an open state to a closed state.

6. The backlight driver chip as claimed in claim 1, wherein, The control module is further configured to: acquire the signal level at the communication connection port of each of the two bidirectional communication modules; when the signal level at the communication connection port of any of the two bidirectional communication modules does not correspond to the signal waveform of the detected signal and there is no intermediate level, determine that the instantaneous signal strength at the communication connection port of that bidirectional communication module is not greater than the preset signal strength.

7. The backlight driver chip as claimed in claim 1, wherein, The control module is further configured to: when the main communication module is set to signal input mode and the slave communication module is set to signal output mode, receive a first control signal from the backlight controller or the next-level backlight driver chip in the backlight control system through the main communication module, and send a second control signal based on the first control signal to the next-level backlight driver chip in the backlight control system through the slave communication module.

8. The backlight driver chip as described in claim 7, wherein, The control module is further configured to: when the main communication module is set to signal output mode and the slave communication module is set to signal input mode, receive a first feedback signal from the next-level backlight driver chip through the slave communication module, and send a second feedback signal based on the first feedback signal to the previous-level backlight driver chip or the backlight controller through the main communication module.

9. A backlight control system, comprising: Backlight controller; And one or more backlight driver chips as described in any one of claims 1 to 8.

10. The backlight control system as described in claim 9, wherein, The backlight controller and the one or more backlight driver chips are cascaded via a single-wire link.

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