A light emitting diode (LED) driving device is provided. The LED driving device includes a rectifier configured to generate a rectified voltage, wherein the rectifier is directly connected to an input node of a light source including LEDs; a regulator configured to output a direct current (DC) power supply voltage using the rectified voltage; a microcontroller including a control terminal and a power terminal, wherein the microcontroller is configured to generate a dimming control signal based on a voltage input, receive the DC power supply voltage through the power terminal and output the dimming control signal through the control terminal; a driver configured to control an LED current to flow through the LEDs based on the dimming control signal; and a switch connected between a control node and a ground node, wherein an output terminal of the regulator and the control terminal are connected to the control node.