US Patent 8362840 Apparatus and methods for biasing a power amplifier

Apparatus and methods for biasing a power amplifier are provided. In one embodiment, a packaged circuit includes a power amplifier, a bond wire electrically connected between a system voltage source and a supply input of the power amplifier, a current source, a reference resistor electrically connected between the system voltage source and the current source, and a comparator. The comparator is configured to compare a sense voltage that is based on a voltage across the bond wire to a reference voltage that is based on a voltage across the reference resistor. The comparator is configured to generate a saturation control signal for clamping a bias current of the power amplifier when the sense voltage exceeds the reference voltage.