LED backlight control system and the backlight driver chip used therein

Abstract

This invention provides an LED backlight control system and a backlight driver chip used therein. The backlight driver chip used in the LED backlight control system includes two communication connection ports having the same circuit structure and a port control unit. The port control unit is configured to, when receiving a preset waveform signal through either of the two communication connection ports, set that communication connection port as the master communication connection port of the backlight driver chip and set the other communication connection port as the slave communication connection port of the backlight driver chip.

Claims

1. A backlight driver chip used in an LED backlight control system, comprising two communication connection ports having the same circuit structure and a port control unit, wherein, The port control unit is configured to, when a preset waveform signal is received through either of the two communication connection ports, set one of the communication connection ports as the main communication connection port of the backlight driver chip and set the other of the two communication connection ports as the slave communication connection port of the backlight driver chip.

2. The backlight driver chip as described in claim 1, wherein, The port control unit is further configured to set the two communication connection ports to input state before the backlight driver chip starts working after being powered on.

3. The backlight driver chip as described in claim 1, wherein, The port control unit is further configured to perform one or more of the following processes when the main communication connection port is set to an input state and the secondary communication connection port is set to an output state: receiving a first control signal from the preceding backlight driver chip or backlight controller in the LED backlight control system through the main communication connection port, and outputting a second control signal to the following backlight driver chip in the LED backlight control system through the secondary communication connection port, wherein the first control signal and the second control signal are generated based on the backlight control signal issued by the backlight controller.

4. The backlight driver chip as described in claim 3, wherein, The port control unit is further configured to perform one or more of the following processes when the main communication connection port is set to an input state and the secondary communication connection port is set to an output state: receiving a first feedback signal from the preceding backlight driver chip in the LED backlight control system through the main communication connection port, and outputting a second feedback signal to the subsequent backlight driver chip or the backlight controller in the LED backlight control system through the secondary communication connection port, wherein the first feedback signal and the second feedback signal are generated based on backlight feedback signals provided by one or more backlight driver chips in the LED backlight control system.

5. The backlight driver chip as claimed in claim 1, wherein, The port control unit is further configured to perform one or more of the following processes when the main communication connection port is set to an output state and the slave communication connection port is set to an input state: receiving a first feedback signal from the subsequent backlight driver chip in the LED backlight control system through the slave communication connection port, and outputting a second feedback signal to the previous backlight driver chip or backlight controller in the LED backlight control system through the main communication connection port, wherein the first feedback signal and the second feedback signal are generated based on backlight feedback signals provided by one or more backlight driver chips in the LED backlight control system.

6. The backlight driver chip as claimed in claim 1, wherein, Each of the two communication connection ports includes a first buffer and a second buffer. The input terminal of the first buffer is connected to the signal output terminal of the port control unit, the enable terminal is connected to the port enable terminal of the port control unit, and the output terminal is connected to the input terminal of the second buffer. The output terminal of the second buffer is connected to the signal input terminal of the port control unit. The output terminal of the first buffer and the input terminal of the second buffer are connected to the input / output terminals of the communication connection port.

7. The backlight driver chip as described in claim 6, wherein, Each of the two communication connection ports further includes a pull-up resistor or a pull-down resistor. The output terminal of the first buffer and the input terminal of the second buffer are connected to the chip power supply voltage of the backlight driver chip through the pull-up resistor or grounded through the pull-down resistor.

8. The backlight driver chip as described in claim 6, wherein, The port control unit is further configured to set the communication connection port to an input or output state by sending an output enable signal to the first buffer. When the output enable signal is valid, the communication connection port is in an output state, and when the output enable signal is invalid, the communication connection port is in an input state.

9. An LED 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 LED 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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