The invention provides an LED constant-current driving device and driving method, which is used for controlling display of an
LED lamp group. The device comprises a
power module, a singlechip
microcomputer, a constant-current driving module, an optical
signal acquisition module, a photoelectrical
signal conversion module, a key control module and a brightness level display module, wherein the constant-current driving module is used for providing a
constant current for the
LED lamp group, the optical
signal acquisition module is used for acquiring an optical signal at
fixed time, the photoelectric signal conversion module is used for receiving the optical signal, controlling a current output from the constant-current driving module according to the optical signal and further controlling a current input into the
LED lamp group so as to adjust the brightness of the LED lamp group, the key control module is used for outputting a manual signal to the singlechip
microcomputer, the singlechipmicrocomputer is used for controlling an output current of the constant-current driving module according to a manual signal and further controlling the current input into the LED lamp group so as toadjust the brightness of the LED lamp group, and the brightness level display module is used for indicating a brightness level of the current LED lamp group. By the device and the method, the servicelifetime of an LED can be prolonged, and energy saving and environmental friendliness can be achieved very well.