A panel driving circuit that produces a panel test pattern and a method of
testing a panel are provided. The driving circuit includes a pattern
generation unit and a selection unit. The pattern generation unit
responds to a system clock and produces pattern test data and pattern
test signals. The selection unit responds to a test signal and selects
and outputs either (a) the pattern test data and the pattern test signals
that are outputted from the pattern generation unit, or (b) the pattern
test data and pattern test signals that are directly applied from the
outside. The driving circuit and the method of the panel test generates
the panel test data, the horizontal synchronizing signal, the vertical
synchronizing signal, and the data activating signal within the driving
circuit using a system clock so that the testing of the panel can be
carried out without using a separate test device.