CURRENT-MODE D/A CONVERTER HAVING VARIABLE OUTPUT AND OFFSET CONTROL

摘要

A current-mode D/A converter is described having variable output and offset control. According to an exemplary embodiment, a first D/A converter includes a number of first control inputs and an output capable of generating a first current proportional to a number of active first control inputs. A driver includes an input connected to the output of the first D/A converter, a number of second control inputs, and an output capable of generating a second current proportional to the first current based on a number of active second control inputs. A second D/A converter includes a number of third control inputs and an output capable of generating a third current proportional to a number of active third control inputs. Offset control circuitry includes an input connected to the output of the second D/A converter, an offset control input, and an output connected to the output of the driver. The offset control circuitry is capable of summing the second and third currents at the output of the driver when the control input is active.