DISPLAY DEVICE, ESPECIALLY MAINTAINING A DRAIN POTENTIAL OF AN OUTPUT TRANSISTOR FUNCTIONING AS A CONSTANT CURRENT SOURCE CONSTANT EVEN IN A SAMPLING PERIOD OF ANOTHER CIRCUIT

摘要

PURPOSE: A display device is provided to maintain a constant drain potential of an output transistor and to suppress the variation due to leakage of gate potential of the output transistor. CONSTITUTION: The display device has a plurality of pixel circuits(101) arranged in a matrix, and a data line(DTL101-DTL10n) arranged in every column of the matrix arrangement of the pixel circuit and supplied with a signal current according to brightness information. A horizontal selector(103) has a plurality of sample hold circuits sampling and holding an input image signal current. The horizontal selector samples and holds an image signal to all sample hold circuits in sequence, and outputs sample-held current value to a corresponding data line. Each sample hold circuit has a field effect transistor whose source is connected to a fixed potential, and the first switch connected between a drain and a gate of the field effect transistor, and the second switch connected between the drain of the field effect transistor and a supply line of the signal current, and a capacitor connected between the gate of the field effect transistor and a fixed potential. The sample hold circuit also has a leak removal circuit supplies a current corresponding to a sampled signal current to the drain of the field effect transistor.