Patent ID: 7215221

Claim:
A method of broadband termination of amplifier harmonics from an active device, comprising: configuring a pi network providing a low impedance at frequency bands above a frequency band of operation while allowing DC bias to be appliable to the active device output, wherein configuring the pi network includes: coupling a low pass filter to an active device drain, the low pass filter having an RF choke and a first capacitor; and coupling a series inductor capacitor resistor resonant circuit in parallel with the low pass filter, the series inductor capacitor resistor resonant circuit having: a resistor valued to provide a load to at least a second harmonic frequency of a desired frequency; a second capacitor being valued to resonate with the RF choke to produce a high impedance at the desired frequency and a low impedance at at least a second harmonic of the desired frequency; and an inductor being valued to resonate with the second capacitor at at least the second harmonic frequency of the desired frequency; and coupling the pi network to the active device output.