| 摘要 |
An amplifier circuit includes a signal summing node, a first amplifier configured to operate in a first mode, an impedance inverter, a second amplifier configured to operate in a second mode and a wideband impedance transformer. The impedance inverter couples an output of the first amplifier to the signal summing node. The impedance inverter is configured to provide impedance transformation and load modulation to the first amplifier. The second amplifier has an output coupled to the signal summing node. The wideband impedance transformer has a first end coupled to the signal summing node and a second end forming a terminal node. The wideband impedance transformer is configured to present a real impedance to the first amplifier over at least 25% of a radio frequency bandwidth of the amplifier circuit. |
