D/A conversion circuit and A/D conversion circuit

A semiconductor device comprising:

• a digital section configured to process a digital signal;
• an analog section configured to process an analog signal;
• and
• an interface section, provided between the digital section and the analog section, configured to include a D/A conversion circuit;
• wherein the D/A conversion circuit comprises:
• a resistor string including a plurality of resistor elements coupled in series between the low-potential power supply and the high-potential power supply;
• a plurality of first switch groups, coupled among the resistor elements, for selectively outputting any divided voltages generated among the resistor elements in accordance with a digital signal, the first switch groups each having a common output coupled to a corresponding one of a plurality of nodes;
• a second switch group, coupled between the plurality of nodes and an output terminal of the D/A conversion circuit, for selectively coupled one of the nodes to the output terminal to output the divided voltage;
• and
• a third switch group, each switch of the third switch group being coupled in parallel with a predetermined switch in a corresponding one of the first switch groups;
• wherein when a switch of the second switch group is turned off, switches of the first switch group that are coupled to the turned-off switch of the second switch group via a corresponding one of the nodes are turned off, and a switch of the third switch group that is coupled to the turned-off switch of the second switch group is turned on to apply a predetermined voltage to the corresponding one of the nodes.