A novel distributed amplifier with high gain, low noise and high output power in 0.18-µm CMOS technology

A new distributed amplifier (DA) topology is proposed. This topology is the combination of the conventional distributed amplifier (CDA) and the cascaded single-stage distributed amplifier (CSSDA), which makes wideband amplifier by considering the gain, noise figure and output power simultaneously. From the measurements, the DA has a small signal gain of 20.5 dB, a 3-dB bandwidth of 35 GHz, and a gain-bandwidth product of 371 GHz. The maximum OP_1dB is 8.6 dBm and the noise figure is between 6.8 and 8 dB at frequency lower than 18 GHz. The chip size including testing pads is only 0.78 mm², and the ratio of the gain-bandwidth to chip size achieves 476 GHz/mm². To authors´ knowledge, the circuit has the highest ratio of gain-bandwidth product to chip area and the highest figure of merit (FOM) in 0.18-μm CMOS, and it has a comparable performance with other DAs in advanced processes.