Peaking amplifier frequency tuning

A peaking amplifier circuit, comprising:

• an input node, an output node, and a feedback node;
• a first input amplifier having an input connected to the input node and an output connected to the feedback node;
• a second input amplifier having an input connected to the input node;
• a coupling capacitor connected between an output of the second input amplifier and the feedback node;
• an amplifier having an input connected to the feedback node and an output connected to the output node;
• a feedback circuit including:
• a base feedback amplifier having an input connected to the output node and an output connected to the feedback node;
• and
• a tunable feedback amplifier having an input connected to the output node and an output connected to the output of the second input amplifier;
• and
• a tuning circuit for varying a transconductance of the feedback circuit to adjust an operational frequency of the peaking amplifier circuit.

A method, comprising:

• adjusting a transconductance of a feedback circuit of a peaking amplifier;
• adjusting an operational frequency of the peaking amplifier in response to the adjustment of the transconductance of the feedback circuit;
• and
• reducing a variation in DC gain attenuation at different operational frequencies of the peaking amplifier,
• wherein the feedback circuit includes a feedback amplifier, and wherein adjusting the transconductance of the feedback circuit includes applying a tuning voltage to the feedback amplifier, the tuning voltage varying a transconductance of the feedback amplifier and causing an adjustment of the operational frequency of the peaking amplifier.