Cree Inc of Durham, NC, USA has introduced what it claims are the industry’s highest-power continuous wave (CW) RF gallium nitride (GaN) high-electron-mobility transistors (HEMTs) packaged in a dual-flat no-leads (DFN) format.
Targeted at the cost-sensitive sub-100W commercial radar and data-link amplifier market segments, the new 6- and 25-watt DFN transistors effectively obsolete the use of inefficient gallium arsenide (GaAs) transistors in C- and X-band frequencies, claims Cree, and also enable the practical replacement of short-life tube-based technology for commercial radar applications such as weather, marine and surveillance.
Based on Cree’s proven 40V, 0.25μm-gate-length high-frequency process, Cree reckons that its GaN DFN transistors deliver twice the saturated output power (PSAT) efficiency and transistor gain of GaAs IMFETs (internally matched field-effect transistors) in a package size that is nearly 20 times smaller at comparable power levels and frequencies. In high-capacity microwave data links used in enterprise, point-to-point and airborne communication networks, the new transistors extend the communication range while delivering twice the linear efficiency of GaAs-based amplifiers. This higher efficiency gives RF designers the flexibility needed to reduce amplifier size and weight, creating savings in operating and total lifecycle costs, says Cree.
“For years, commercial microwave radar transmitters have been plagued with the compromised field life of tube-based amplifiers that carry significant maintenance costs,” says Tom Dekker, Cree’s director of RF sales & marketing. “Historically, high-capacity data links were limited to the use of inefficient GaAs IMFETs,” he adds. “By delivering superior efficiency and power capabilities at an affordable price, our new GaN DFN transistors enable for the first time the replacement of these legacy technologies in lower-power, cost-sensitive commercial systems.”
The new DFN devices can also make act as drivers for Cree’s CGHV96100 and CGHV96050F2 fully matched FETs for X-band frequencies, enabling the output- and drive-stage transistors to operate from the same voltage rail. This allows convenient, regulated power distribution to economize board space compared with a mixed-voltage transistor line up.
Samples and reference designs for C- and X-band are available now utilizing the CGHV1F006S (6W) and CGHV1F025S (25W) GaN DFN transistors. Large-signal models are also available for Agilent’s ADS and AWR Microwave Office simulators.
