D/A CONVERTER, AND SUCCESSIVE APPROXIMATION TYPE A/D CONVERTER

摘要

PROBLEM TO BE SOLVED: To enhance the non-linearity of an analog output signal with respect to a digital input signal. SOLUTION: The D/A converter includes: a first resistor which outputs an analog output signal corresponding to a digital input signal from any selected one of connecting points of series connection of a plurality of first resistance 11 each having a first resistance value; a second resistor which is connected to a power supply potential side of the first resistor and in which any one of a plurality of second resistance values is selected; a third resistor which is connected to a ground potential side of the first resistor and in which any one of a plurality of third resistance values is selected; a control circuit which selects any one of the connecting points of the plurality of first resistance in the first resistor in accordance with the digital input signal and performs control so that the total of second and third resistance values selected at the second and third resistors becomes a predetermined value; and a variable resistor 18 which is connected in parallel with the first resistor and to which such a variable resistance value is set as to linearly change the analog output signal in accordance with the digital input signal. COPYRIGHT: (C)2009,JPO&INPIT