The effect of device configuration on GaAs MESFET negative resistance behaviour

A new analysis of the effect of device configuration on negative resistance behaviour of a GaAs MESFET with series feedback has been undertaken. The analysis is based on a simplified equivalent circuit representation of the active device, and gives explicit results for the frequency range over which negative resistance behaviour can be expected to occur. It is shown that even with S/sub 12/=0, the device can produce negative resistance if the correct feedback termination is used. Furthermore, it is shown that capacitive series feedback cannot be used to generate negative resistance in the common gate and common drain configurations.<
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