Power amplifier

A power amplifier, comprising:

• a power transistor;
• a bias circuit comprising a first transistor configured to provide a bias current to an input terminal of the power transistor;
• and
• a current limiting circuit configured to reduce the bias current when an output current of the power transistor exceeds a threshold value,
• wherein the current limiting circuit comprises:
• a second transistor comprising a collector connected to a base of the first transistor and a base connected to the input terminal of the power transistor.

A power amplifier, comprising:

• a bias circuit, comprising a first transistor;
• a current limiting circuit comprising a current limiting transistor;
• and
• a power transistor;
• wherein:
• a collector of the current limiting transistor is connected to a base of the first transistor,
• a base of the current limiting transistor is connected to an emitter of the first transistor and an input terminal of the power transistor, and
• the current limiting transistor is configured to generate a sink current to reduce a bias current of the power transistor when an output current of the power transistor exceeds a threshold value.