Patent ID: 7911225

Claim:
A data output device, comprising: a pre-driver unit configured to control a driving force according to an impedance control signal and drive data to output by the driving force, the pre-driver unit comprising: a pre-driver configured to drive the data to output; and a driving force controller of which driving is controlled according to the impedance control signal to correct and output a slew rate of a signal outputted from the pre-driver; and a main-driver unit configured to control an impedance according to pull-up and pull-down resistance control codes having values that correspond to the impedance control signal and to drive an output of the pre-driver unit by using the controlled impedance, wherein the impedance control signal is an address signal provided from a mode register in order to set any one of a first resistance value and a second resistance value as the impedance, the second resistance value being larger than the first resistance value, wherein the main-driver unit includes: a main-driver configured to drive an output from the pre-driver unit; a pull-up resistor which is connected between a power voltage terminal and an output terminal of the main-driver and controls a pull-up resistance of the impedance according to the pull-up resistance control code; and a pull-down resistor which is connected between a ground voltage terminal and the output terminal of the main-driver and controls a pull-down resistance of the impedance according to the pull-down resistance control code.