Digital-to-analog converter

A resistor string digital-to-analog converter, comprising:

• (a) an input terminal configured to receive a digitally coded digital input signal;
• (b) an output terminal configured to output an analog output voltage signal;
• (c) a plurality of voltage acquisition nodes;
• (d) a plurality of resistors which are connected in series via the plurality of voltage acquisition nodes,
• (e) a pair of intermediate nodes, wherein a first intermediate node of the pair of intermediate nodes is associated with a first intermediate analog voltage and a second intermediate node of the pair of intermediate nodes is associated with a second intermediate analog voltage;
• (f) a high-order voltage-acquisition circuit configured to provide conduction between the plurality of voltage acquisition nodes and the pair of intermediate nodes based on the digital input signal;
• and
• (g) a low-order converter configured to generate the analog output voltage signal by interpolating between the first intermediate analog voltage and the second intermediate analog voltage based on the digital input signal.

A method for converting a digitally coded digital input signal into an analog output voltage signal by using a high-order voltage-acquisition circuit and a low-order converter, comprising:

• inputting the digital input signal into each of the high-order voltage-acquisition circuit and the low-order converter;
• using the high-order voltage-acquisition circuit to receive a plurality of voltages via each of a plurality of input voltage acquisition nodes via which each of a plurality of resistors is connected in series, and to use the received plurality of voltages and the digital input signal to generate a first intermediate analog voltage at a first intermediate node and a second intermediate analog voltage at a second intermediate node;
• and
• using the low-order converter to receive the first intermediate analog voltage from the first intermediate node and the second intermediate analog voltage from the second intermediate node, and to interpolate between the first intermediate analog voltage and the second intermediate analog voltage based on the digital input signal in order to generate the analog output voltage signal.