Patent ID: 8228223
Filing Date: 2012-07-24
Classification: H03M

Abstract:
1. A resistor string digital-to-analog converter comprising: a high-order resistor string that generates a plurality of high-order analog voltages, which are obtained by dividing a first reference voltage and a second reference voltage with unit resistors, and outputs the high-order analog voltages from a plurality of voltage acquisition points coupled through one or more of the unit resistors; first high-order switches that are provided for the voltage acquisition points on a one-to-one basis, the conduction state of the first high-order switches being controlled in accordance with a first high-order control signal; a high-order decoder that generates the first high-order control signal in accordance with the value of a high-order bit of a digital input signal, which indicates one value with a plurality of bits, and brings a pair of the first high-order switches into conduction in accordance with the first high-order control signal; a low-order decoder that generates a low-order control signal corresponding to a value containing at least the lowest-order bit of the digital input signal; a conversion unit that outputs a voltage between a pair of analog voltage values, which are obtained through the pair of the first high-order switches, in accordance with the low-order control signal; wherein the high-order decoder brings into conduction a pair of the first high-order switches corresponding to a high-order analog voltage output from the voltage acquisition points adjacent to each other through one or more of the voltage acquisition points.