A three-stage cascaded distributed amplifier with GBW exceeding 1.5THz

A three-stage cascaded distributed amplifier is designed in a 0.13μm SiGe BiCMOS process. By optimizing the amplifier both at the architecture and element level, an extremely large measured gain-bandwidth product in excess of 1.5THz is obtained. The core amplifier consumes 75mA from a 3.3V supply and provides an average gain of 24dB from 15GHz to at least 110GHz (limited by equipment BW). A distributed RF-choke design is employed to provide the bias current to the three cascaded stages. The pass-band gain stays between 23 and 26.5dB.