Cree Inc of Durham,NC,USA has launched a 40V,0.25µm,GaN-on-SiC HEMT process die product family,with power and bandwidth capabilities through the Ku-band that enables the replacement of travel-wave tubes with solid-state amplifiers(yielding improved efficiency and reliability).The firm is showcasing its performance capabilities in booth 2125 at the 2012 IEEE International Microwave Symposium in Montreal,Canada(17-22 June).
"Cree's 0.25µm GaN HEMT die product family offers significant improvements in gain,efficiency and power density compared to GaAs transistors over the same frequency range,"claims Tom Dekker,director RF sales&marketing."The higher gain allows for more effective power-combining schemes and enables solid-state power amplifiers to be produced with hundreds to multi-kilowatts at C-band,X-band and Ku-band,"he adds.
Applications include marine radar,medical imaging,industrial and satellite communication.Compared to GaAs transistors,solid-state amplifiers can improve reliability,reduce costs and boost efficiency while shrinking the size of not only the power amplifier but also the power supply.The higher efficiency of GaN HEMT power amplifiers can result in reduced transmitter power consumption.
"Cree's 0.25µm GaN HEMT products demonstrate breakthrough performance in improved efficiency and bandwidth by enabling new classes of transistor operation not achievable with GaAs-based transistors,"claims RF business development manager Ray Pengelly."Good examples are switch-mode HPAs,which have been reported to offer greater than 80%power-added efficiency at microwave frequencies,"he adds."GaN HEMT HPAs have been produced with instantaneous bandwidths from 6 to 18GHz at power levels exceeding 10W.These 0.25µm GaN performance levels provide system engineers leapfrog advantages to re-invent their GaAs and tube transmitters."
The new GaN HEMT die products(CGHV1J006D,CGHV1J025D and CGHV1J070D)are rated at output powers of 6W,25W and 70W at a drain voltage of 40V with an operating frequency range through the Ku-band.
This latest die family is supported by Cree's proprietary,scalable large-signal device models that are compatible with Agilent Technologies'Advanced Design System(ADS)and AWR's Microwave Office simulator platforms,enabling RF design engineers to accurately simulate advanced RF amplifier circuits,which can significantly reduce design cycle times(a most desirable requirement for the higher microwave frequencies).The 0.25µm GaN-on-SiC HEMT process has been qualified to operate up to a drain voltage of 40V with what is claimed to be industry-leading reliability.The mean-time-to-failure exceeds more than 1 million hours at channel temperatures up to 225°C.
