A display driving circuit to supply a gray scale voltage corresponding to display data to a display panel, the display driving circuit including: a generation circuit to divide a reference voltage to generate a plurality of levels of the gray scale voltages; an interface circuit; a selection circuit to select the gray scale voltage corresponding to the display data from the plurality of levels of voltages; a first register to store a setting value that adjusts the amplitude of a gamma characteristic curve from outside via the interface circuit; and a second register to store a setting value that adjusts the gradient of the gamma characteristic curve from outside via the interface circuit; and a third register to store a setting value for micro adjusting the gamma characteristic curve from outside via the interface circuit; wherein the first, second and third registers are assigned different addresses.