Patent attributes
A display driving device includes: a tone voltage generating circuit generating as many standard voltages as tones; and a DA converter circuit selecting one of the standard voltages in accordance with display data and outputting the selected standard voltage, and applies a tone display voltage to data signal lines of an active matrix scheme display panel. In the tone voltage generating circuit are there provided: a resistance dividing circuit generating as many standard voltages as tones, the standard voltages having voltage values between an upper limit voltage and a lower limit voltage; and an adjusting circuit generating the upper limit voltage and the lower limit voltage. A reference voltage regulated by an electronic volume control provided externally to the tone voltage generating circuit is supplied to the adjusting circuit, and both the upper limit voltage and the lower limit voltage are varied in accordance with the reference voltage. This makes it possible to provide a display driving device, as well as a display using it, which readily allows for changes in γ characteristics in accordance with the characteristics of the liquid crystal material and the liquid crystal panel without additional manufacturing cost.
