Analysis of the oscillation conditions in distributed amplifiers

Author

Gamand, Patrice

Author_Institution

Lab. d´´Electron. et de Phys. Appl., Limeil-Brevannes, France

Volume

37

Issue

3

fYear

1989

fDate

3/1/1989 12:00:00 AM

Firstpage

637

Lastpage

640

Abstract

It has been shown that under certain conditions oscillation phenomena can occur in distributed amplifiers. It has also been demonstrated, using a simplified transistor model and a symmetrical amplifier with lumped circuit elements, that the oscillation depends directly on the transconductance g_m of the active devices. The origin of this oscillation was found to be the loop formed in the distributed amplifier structure. The analysis has been experimentally verified in a practical 1-20-GHz monolithic MESFET amplifier. Finally, design guidelines have been established to avoid stability problems and to improve the capabilities of high-gain distributed amplifiers

Keywords

MMIC; Schottky gate field effect transistors; circuit oscillations; field effect integrated circuits; microwave amplifiers; 1 to 20 GHz; distributed amplifiers; lumped circuit elements; monolithic MESFET amplifier; oscillation conditions; stability; symmetrical amplifier; transconductance; transistor model; Circuits; Coaxial components; Conductors; Distributed amplifiers; Eigenvalues and eigenfunctions; Impedance; Microwave theory and techniques; Transmission line theory; Transmission lines; Wire;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.21642

Filename

21642