DIGITAL TO ANALOG CONVERSION

摘要

A unit cell for a digital to analog conversion circuit comprising; a current source (CS); a first data switch (S1) coupled to the current source (CS); a second data switch (S2) coupled to the current source (CS); a first phase switch (Phi1) coupled between the current source (CS) and the first data switch (S1); a second phase switch (Phi2) coupled between the current source (CS) and the second data switch (S2); a controller arranged to switch between the first (Phi1) and second (Phi2) phase switches in a Break Before Make alternating sequence, and to switch the first (S1) and second (S2) data switches in a Make Before Break sequence. A digital to analog convector circuit constructed using unit cells according to the invention is more area and power efficient than the previously known circuit because it uses only one current source, yet it succeeds in preventing short-circuit error currents between the outputs and solves the problems caused by pulse asymmetry and the influence of switch-charge injection, and provides more linear and better quality output signals.