Differential source follower driven power amplifier

A power amplification device, comprising:

• a power amplifier core stage;
• a power amplifier driver stage configured to receive a radio frequency signal to be amplified by the power amplification device, the power amplifier driver stage including a set of transistors including a first source follower input transistor and a first current source transistor, a source of the first source follower input transistor coupled to a drain of the first current source transistor, the source of the first source follower input transistor directly coupled to the power amplifier core stage to drive the power amplifier core stage, in which the first source follower input transistor is configured to provide a bias signal and at least a portion of the radio frequency signal to at least one transistor of the power amplifier core stage;
• means for transforming a voltage associated with the radio frequency signal coupled to the power amplifier driver stage to generate a voltage gain at an input of the power amplifier driver stage;
• and
• means for generating a first bias signal to bias the power amplifier driver stage.

A method of performing signal amplification by a power amplification device, comprising:

• generating alternating current based radio frequency signals to drive differential source follower transistors and associated current source transistors, the alternating current based radio frequency signals based at least in part on differential radio frequency signals to be amplified by the power amplification device;
• matching an impedance of the differential source follower transistors to a characteristic impedance of a passive network driving the differential source follower transistors and the associated current source transistors;
• generating a passive voltage gain at inputs of the differential source follower transistors;
• and
• generating drive signals at outputs of the differential source follower transistors to drive a power amplifier core stage of the power amplification device, the drive signals based at least in part on the passive voltage gain and the alternating current based radio frequency signals.

A power amplification device, comprising:

• a power amplifier core stage;
• a power amplifier driver stage configured to receive a radio frequency signal to be amplified by the power amplification device, the power amplifier driver stage including a set of transistors including a first source follower input transistor, a second source follower input transistor, a first current source transistor and a second current source transistor, a source of the first source follower input transistor coupled to a drain of the first current source transistor, the source of the first source follower input transistor and a source of the second source follower input transistor directly coupled to the power amplifier core stage to drive the power amplifier core stage, the set of transistors arranged in a differential configuration to generate differential signals to drive the power amplifier core stage;
• an input match and passive voltage gain device coupled to the power amplifier driver stage to generate a voltage gain at an input of the power amplifier driver stage, the input match and passive voltage gain device comprising a transformer positioned between a first pairing of the first source follower input transistor and the first current source transistor and a second pairing of the second source follower input transistor and the second current source transistor;
• and
• a first bias source configured to generate a first bias signal to bias the power amplifier driver stage.