Methods and circuitry for reducing mixer harmonics conversion gain and local oscillator fundamental and harmonics feedthrough

Mixer circuitry comprising:

• a first pair of transistors coupled to a first tail node and having first gate terminals configured to receive a local oscillator signal;
• a second pair of transistors coupled to a second tail node and having second gate terminals configured to receive the local oscillator signal;
• a first digital-to-analog converter (DAC);
• a second digital-to-analog converter (DAC) coupled between the first DAC and the first gate terminals of the first pair of transistors;
• and
• a third digital-to-analog converter (DAC) coupled between the first DAC and the second gate terminals of the second pair of transistors.

A method of operating mixer circuitry, comprising:

• receiving a first oscillating signal at a gate terminal of a first mixer transistor;
• receiving a second oscillating signal at a gate terminal of a second mixer transistor, the first and second mixer transistors coupled to a first tail node;
• and
• with a second digital-to-analog converter (DAC), receiving a bias voltage from a first digital-to-analog converter (DAC), outputting a first bias voltage to the gate terminal of the first mixer transistor, and outputting a second bias voltage to the gate terminal of the second mixer transistor.