Source driver circuit of liquid crystal display device

The present invention relates to a technique for preventing noise data from being displayed before valid data is inputted when a liquid crystal display device is powered on. The invention comprises: a power voltage input unit which divides a VCC power voltage and a VDD power voltage, and outputs the divided voltages, wherein the voltages are divided and outputted by setting an intermediate level of the VDD power voltage to be lower than a level of the VCC power voltage; a power voltage comparator which compares the voltages inputted after having been divided by the power voltage input unit, and outputs an output voltage in a "high" state at a section in which the level of the VCC power voltage is shown in the higher state than the intermediate level of the VDD power voltage; a Schmitt trigger which outputs the output voltage of the power voltage comparator as a reset signal, wherein it prevents the reset signal to sensitively react to the external environment; and a particular voltage supplier which outputs a voltage of a particular level at a section between a first gate start pulse and the reset signal inputted from the Schmitt trigger.