Patent ID: 8907902

Claim:
An electronic device, comprising: a first display to display files; a second display comprising at least two display areas and at least two light-emitting diode (LED) backlight modules, each of the at least two display areas corresponding to one of the at least two LED backlight modules, and each of the at least two display areas being configured to display option icons of an option type to control the files displayed on the first display; a storage unit configured to store a file type-option type table and an option type-LED backlight module table, the file type-option type table recording relationship between the file types and the option types, each of the file types corresponds to at least one option type, and the option type-LED backlight module table recording relationship between the option types and the LED backlight modules, each of the option types corresponding to one of the LED backlight modules; a processor configured to: determine the file type of a file currently displayed on the first display and determine which of the option types the determined file type corresponds to according to the file type-option type table; determine which LED backlight module each of the at least one determined option type corresponds to according to the option type-LED backlight module table; and output control signals to an LED driving circuit to turn on at least one of the determined LED backlight modules; wherein, the LED driving circuit comprises a power providing module and a driving module, the power providing module is configured to provide power to the LED driving circuit, the driving module is configured to receive the control signals and turn on the at least one of the determined LED backlight modules, the power providing module further comprises a control chip, the control chip comprises a feedback port and an output port, the value of the voltage of the feedback port is constant, and the control chip outputs a driving current to turn on the at least one of the determined LED backlight modules, the value of the driving current is determined according to the value of the current of the feedback port.