Digital-to-analog converters with triode switches

A digital-to-analog converter (DAC), comprising:

• a plurality of current steering DAC unit cells, each of the plurality of current steering DAC unit cells comprising:
• a resistor;
• first, second, third and fourth current paths, each current path comprising a current steering switch coupled to the resistor and an output transistor coupled to the respective current steering switch;
• a plurality of reset switches coupled between respective current steering switches and output transistors of the current paths;
• and
• a plurality of current sources coupled to respective current steering switches of the current paths;
• and
• a controller configured to bias the current steering switches of the plurality of current paths so that transistors within the current steering switches operate in triode region sequentially;
• wherein biasing the switches of the plurality of current paths in triode sequentially comprises:
• at a first time, biasing the current steering switch of the first current path in triode and deactivating each of the current steering switches of the second, third and fourth current paths, and activating the reset switch of the third current path and deactivating each of the reset switches of the first, second and fourth current paths;
• and
• at a second time, biasing the current steering switch of the third current path in triode and deactivating each of the current steering switches of the first, second, and fourth current paths, and activating the reset switch of the first current path.

A method for controlling a digital-to-analog converter (DAC) comprising a plurality of DAC unit cells, at least one of the plurality of DAC unit cells comprising first, second, third and fourth current paths, each current path comprising a current steering switch and an output transistor coupled to the current steering switch, the method comprising:

• at a first time, biasing the current steering switch of the first current path so that a transistor within the current steering switch of the first current path operates in triode region and deactivating each of the current steering switches of the second, third and fourth current paths;
• and
• at a second time, biasing the current steering switch of the third current path so that a transistor within the current steering switch of the third current path operates in triode region and deactivating each of the current steering switches of the first, second, and fourth current paths;
• wherein each of the first, second, third and fourth current paths comprises a reset switch coupled between the respective current steering switch and the respective output transistor, further comprising:
• at the first time, activating the reset switch of the third current path and deactivating each of the reset switches of the first, second and fourth current paths;
• and
• at the second time, activating the reset switch of the first current path.