Dual-string digital-to-analog converters (DACs), and related circuits, systems, and methods

摘要

Dual-string digital-to-analog converters (DACs), and related circuits, systems, and methods are disclosed. In embodiments disclosed herein, a primary voltage divider of the dual string-DAC is comprised of at least one adjusting circuit. The adjusting circuit is configured to maintain the ideal voltage of a selected resistor node pair across a secondary voltage divider circuit in response to a primary switch unit selecting a selected resistor node pair. In this manner, impedance isolation is not required between a primary voltage divider and the secondary voltage divider circuit of the dual-string DAC. As a result, as non-limiting examples, the area on an integrated circuit (IC) for a dual-string DAC may be decreased, power consumption of the DAC may be decreased, and/or the dual-string DAC may have increased performance by not requiring a settling time.

主权项

1. A method of dividing voltage in a dual-string digital-to-analog converter (DAC), comprising:
dividing a total voltage, a primary resistor string having a total resistance, the primary resistor string comprising a plurality of resistor nodes configured to divide a DAC input voltage applied across the primary resistor string into a plurality of divided voltage levels; selecting a resistor node circuit comprising a selected resistor node pair among the plurality of resistor nodes of the primary resistor string based on a DAC input code to couple a divided voltage level across the selected resistor node pair to a secondary voltage divider circuit of a dual-string DAC; adjusting a resistance of the selected resistor node pair with at least one first fractional resistance to maintain an ideal voltage of the selected resistor node pair across the secondary voltage divider circuit in response to a primary switch unit selecting the selected resistor node pair; and not isolating a primary voltage divider from the secondary voltage divider circuit.