RF active balun circuit for improving small-signal linearity

A pre-distortion circuit to improve linearity of an input signal, comprising:

• an input terminal arranged to receive an input signal;
• an output terminal arranged to produce an output signal;
• a signal amplifier arranged to amplify the input signal, via the input terminal, and to generate the output signal, via the output terminal, said signal amplifier comprising at least two transistors arranged in a cascade and driven by first and second gate voltages for cascade amplification;
• a distortion signal generator arranged to linearize the output signal to remove nonlinear components from the output signal;
• and
• an insulator provided to insulate the signal amplifier from a third gate voltage applied to the distortion signal generator.

A pre-distortion circuit to improve linearity of an input signal, comprising:

• an input terminal arranged to receive an input signal;
• an output terminal arranged to produce an output signal;
• a signal amplifier arranged to amplify the input signal, via the input terminal, and to generate the output signal, via the output terminal, said signal amplifier comprising:
• a first transistor having a gate coupled to the input terminal and driven by a first gate voltage, and a drain coupled to ground;
• and
• a second transistor having a gate driven by a second gate voltage, a drain coupled to the output terminal, and a source coupled to a source of the first transistor;
• a distortion signal generator arranged to linearize the output signal to remove nonlinear components from the output signal;
• and
• an insulator provided to insulate the signal amplifier from a third gate voltage applied to the distortion signal generator.