Title :
A broadband low noise dual gate FET distributed amplifier
Author :
Thompson, William J.
Author_Institution :
Texas Instrum. Inc., Dallas, TX, USA
Abstract :
A 2 to 18 GHz monolithic GaAs low-noise distributed amplifier with 10 dB nominal gain was designed and built using the standard Texas Instrument GaAs foundry process. This process incorporates ground vias, metal-insulator-metal (MIM) capacitors and air bridges. The amplifier uses 0.5- mu m-gate ion-implanted dual-gate FETs (DGFETs). The noise figure is less than 5.7 dB over the 2 to 18 GHz band and less than 4.0 dB from 3 to 13 GHz. The DGFET amplifier provides gain control capability; with 5 V and 60 mA operating bias it provides 10-dB nominal gain, input return loss better than 10 dB, and output return loss better than 8 dB. Lower power consumption was demonstrated at 5 V and 30 mA. With this reduced bias the nominal gain drops to 8 dB and the noise figure degrades by 0.3 dB. Increasing the bias to 7 V and 90 mA increases the nominal gain to 11 dB while degrading the noise figure by 0.3 dB. This increased bias gives the amplifier medium power capability, with a 1-dB gain compression power output of 18 dBm at 18 GHz. This increases to 19 dBm for frequencies below 15 GHz.<>
Keywords :
III-V semiconductors; MMIC; field effect integrated circuits; gallium arsenide; microwave amplifiers; wideband amplifiers; 0.5 micron; 10 dB; 2 to 18 GHz; 30 to 90 mA; 5 to 7 V; 5.7 dB; DGFET amplifier; GaAs; MIM; SHF; air bridges; broadband amplifiers; capacitors; compression power output; dual gate FET; dual-gate FETs; gain control capability; ground vias; input return loss; ion-implanted; low noise amplifiers; low-noise distributed amplifier; medium power capability; metal-insulator-metal; noise figure; output return loss; power consumption; reduced bias; semiconductors; standard Texas Instrument GaAs foundry process; Degradation; Distributed amplifiers; FETs; Foundries; Gain; Gallium arsenide; Instruments; MIM capacitors; Metal-insulator structures; Noise figure;
Conference_Titel :
Microwave and Millimeter-Wave Monolithic Circuits Symposium, 1989. Digest of Papers., IEEE 1989
Conference_Location :
Long Beach, CA, USA
DOI :
10.1109/MCS.1989.37252