Provided is a data driver, a driving method of the data driver, and a display device. The data driver includes a latch unit configured to store n-bit image data, wherein n≥2; a conversion unit configured to convert N-bit digital data including the n-bit image data and variable m-bit pseudo control data into an analog voltage and then output the analog voltage, wherein m≥1; and an output unit configured to output a data voltage based on the analog voltage. The data driver is capable of supplying a high image quality based on N-bit digital data with a small circuit size that is based on n-bit image data.