CALIBRATION TECHNIQUE FOR CURRENT STEERING DAC

摘要

In described examples, a current steering digital to analog converter (DAC) (200) includes DAC elements. At least one DAC element (204) is coupled to a calibration circuit (240). The calibration circuit (240) includes a fixed current source (232) coupled to a primary node (220) of the DAC element (204) through a first estimation switch (234). A digital code generator (242) is coupled to the primary node (220), and generates a first digital code corresponding to a primary voltage generated at the primary node (220). The digital code generator (242) generates a second digital code. A correction DAC (250) is coupled to the digital code generator (242) and generates a bias voltage based on the second digital code. The bias voltage is provided to the DAC element (204), so that a current flowing through each of the DAC elements is equal.