Patent attributes
Octagonal phase rotator includes an I-mixer having an I-DAC for steering current between positive and negative phases of an in-phase signal depending on k I-DAC control bits of a control code, a Q-mixer having a Q-DAC for steering current between the positive/negative phases of a quadrature signal depending on k Q-DAC control bits of the code, and an IQ-mixer having n IQ-mixer units each comprising an IQ-DAC for switching a second current unit between the in-phase and quadrature signals, in dependence on a respective bit of n IQ-DAC control bits, and between the positive/negative phases of the in-phase and quadrature signals via I and Q polarity switches respectively of that component. I and Q polarity switches of some different IQ-DAC components switch depending on different I-DAC control bits and Q-DAC control bits respectively. A summation circuit sums weighted output signals from the mixers to produce an output signal of phase.
