PSEUDO-DIFFERENTIAL CLASS-AB DIGITAL-TO-ANALOG CONVERTER WITH CODE DEPENDENT DC CURRENT

摘要

A digital-to-analog converter, RF transmit channel and method, for converting a digital signal of N bits having a set M of most significant bits and a set L of least significant bits to an analog signal, are disclosed. The digital signal defines a set of coded values which are converted to analog values and modulated on to a RF signal. The digital-to-analog converter includes a plurality of switches and an output stage, for providing at least a first differential output signal and a second differential output signal. The output stage modifies currents received from the plurality of switches, such that the value of the average output current of the first and second differential outputs signals is steered to a relatively low current value at the mid-point of the coded values.