A data driving apparatus of an organic electro luminescence display (OELD) panel provides a current to the OELD panel, causing the OELD panel to display pictures. The data driving apparatus may include a data driver for applying data signals using a substantially uniform current; and a data signal controller circuit integrated with the OELD panel for charging and controlling the substantially uniform current in response to the data signals outputted from the data driver so as to apply the data signals to the organic electro luminescence display panel.