Light emitting diode driving device

A LED driving device disposed to a LED lamp board to drive and linearly regulate an illumination brightness of at least one LED, the LED driving device comprising:

• a rectification circuit electrically connected to an alternating current power and disposed with a filter and a rectifier, a rectified voltage capable of being converted into variable constant current being outputted by the rectifier after the filter filtering impulses by receiving an alternating current voltage;
• a holding current circuit coupled to the rectification circuit and disposed with a current switch, the holding current circuit receiving the rectified voltage to output a holding current to the rectification circuit while conducting the current switch;
• and
• a driving circuit coupled to the holding current circuit and the LED, the driving circuit disposed with a filter capacitor, a transistor, a control chip, and a sensing resistor, the filter capacitor receiving and filtering the rectified voltage to form a driving current, the driving current outputted to the LED, the sensing resistor sensing the driving current to form a control signal to conduct or discontinue the current switch,
• wherein, an end of the LED is directly cascaded to a drain of the transistor, and then coupled to an input pin of the control chip after cascading the sensing resistor through a source of the transistor.