Broadband power amplifier and matching network for multi-band millimeter-wave 5g communication

A two-stage power amplifier (PA), the PA comprising:

• a first amplifier stage;
• a second amplifier stage;
• a first matching network circuit coupled in between the first amplifier stage and the second amplifier stage;
• and
• a second matching network circuit coupled to an output port of the second amplifier stage, wherein the second matching network circuit comprises:
• a first capacitor coupled, in parallel, to an input port of the second matching network circuit;
• a broadband on-chip transformer coupled, in parallel, to the first capacitor, wherein the broadband on-chip transformer includes a primary winding and a secondary winding, wherein the secondary winding is a partial winding;
• and
• a second capacitor coupled, in series, in between the broadband on-chip transformer and an output port of the second matching network circuit.

A radio frequency (RF) frontend circuit comprising a power amplifier to amplifier a transmitted signal, the power amplifier comprising:

• a first amplifier stage;
• a second amplifier stage;
• a first matching network circuit coupled in between the first amplifier stage and the second amplifier stage;
• and
• a second matching network circuit coupled to an output port of the second amplifier stage, wherein the second matching network circuit comprises:
• a first capacitor coupled, in parallel, to an input port of the second matching network circuit;
• a broadband on-chip transformer coupled, in parallel, to the first capacitor, wherein the broadband on-chip transformer includes a primary winding and a secondary winding, wherein the secondary winding is a partial winding;
• and
• a second capacitor coupled, in series, in between the broadband on-chip transformer and an output port of the second matching network circuit.