Patent ID: 8362935

Claim:
A device for controlling a reference voltage of a digital-to-analog converter, comprising: an internal chip having an internal memory and a digital-to-analog converter for forwarding an analog voltage to each of a plurality of channels by a reference voltage; a reference voltage adjusting value estimating unit for measuring the voltage from the internal chip to each of the channels, estimating a maximum value and a minimum value thereof primarily, and estimating a reference voltage adjusting value which can minimize a variation between the channels with reference to the reference voltage based on the estimated maximum value and minimum value; and a code generating unit for generating two kinds of code values of a coarse TRIM value which corrects the reference voltage in a great scale and a fine TRIM value which corrects the reference voltage in a fine scale based on the reference voltage adjusting value from the reference voltage adjusting value estimating unit, and storing the two kinds of code values at a designated address of the internal memory for controlling the reference voltage.