Patent ID: 7009454

Claim:
A method for amplifying comprising: operating a first amplifier comprising a first active device supplying a first signal to a first matching network, the first matching network producing a first output, the first matching network including a first set of devices having a first resonance at a normal operating frequency of the circuit; and operating a second amplifier comprising a second active device supplying a second signal to a second matching network, the second matching network producing a second output, the second matching network including a second set of devices having a second resonance at the normal operating frequency of the circuit; wherein the respective outputs of the first and second amplifiers are summed at a summing node to produce a summed signal and, wherein a circuit output signal is derived from the summed signal and, wherein the method has at least a first operating mode and a second operating mode and, wherein whenever the method is in the first operating mode: the first and second active devices are biased to be active and turned on and, wherein whenever the method is in the second operating mode: the second active device is biased into at least a partially cutoff condition and the second matching network presents high impedance at the summing node, the high impedance being caused by the second resonance at the normal operating frequency; wherein the first matching network is a high-pass “π” match structure; whereby the circuit operates with high efficiency and higher power in the first operating mode and the circuit operates with high efficiency and lower power in the second operating mode.