Backlight, control method for backlight, and display device

A display device comprising a display panel and a backlight, wherein the backlight comprise:

• a plurality of light-emitting modules arranged in an array, each of the light-emitting modules comprising a light-emitting unit and a control circuit, the control circuit comprising n branches, a controller and a current module, each of the n branches, the light-emitting unit and the current module being connected in series, each of the n branches provided with a switch, the controller being connected with the switch on each of the branches and configured to control the switch on each of the branches to be turned on or turn off, and the current module being configured to be connected with a power supply;
• wherein each of the n branches corresponds to a different amplitude of current, and when the switch of any one of the n branches is turned on under the control of the controller, the current module inputs to a corresponding branch with a current of a given amplitude, where n is an integer equal to or larger than 2,
• wherein the current module comprises a constant current source circuit,
• the control circuit further comprises a digital-to-analog converter disposed on the control line, and
• the digital-to-analog converter is configured to convert digital signals output by the controller into analog signals and input the analog signals into the constant current source circuit.

A method of controlling a backlight used to control a controller of a backlight, wherein the backlight comprises:

• a plurality of light-emitting modules arranged in an array, each of the light-emitting modules comprising a light-emitting unit and a control circuit, the control circuit comprising n branches, a controller and a current module, each of the n branches, the light-emitting unit and the current module being connected in series, each of the n branches provided with a switch, the controller being connected with the switch on each of the branches and configured to control the switch on each of the branches to be turned on or turn off, and the current module being configured to be connected with a power supply;
• wherein each of the n branches corresponds to a different amplitude of current, and when the switch of any one of the n branches is turned on under the control of the controller, the current module inputs to a corresponding branch with a current of a given amplitude, where n is an integer equal to or larger than 2,
• wherein the current module comprises a constant current source circuit,
• the control circuit further comprises a digital-to-analog converter disposed on the control line, and
• the digital-to-analog converter is configured to convert digital signals output by the controller into analog signals and input the analog signals into the constant current source circuit;
• and wherein the method comprises:
• acquiring a control signal by the controller;
• and
• controlling the switches on the n branches by the controller to turn on the branch as indicated by the control signal to be turned on.