Comparative Analysis of Noise in MODFET and MESFET

In this paper a comparative analysis of effect of noise in MODFET and MESFET was carried out. Noise is inherent in the device because of various reasons such as leakage current, drifting of charge carriers randomly in the drift space and also because of the charge transportation. There are different kinds of noise which affect the performance of the devices at low and higher frequencies. In this paper, the effect of noise at the input and output of MODFET and MESFET w.r.t to frequency is analyzed. Results are analyzed at 3GHz and 9GHz, because the influence of shot noise will be higher at higher frequencies, whereas flicker noise is higher at lower frequencies. Results show that the effect of noise is more on the MESFET when compared with the MODFET. The effect of noise on the drain characteristics of modfet is also analyzed, where the maximum drain current without the influence of the noise is observed to be 130mA, whereas under the influence of noise, it is observed as 15uA. The work is carried out using PSPICE AD of Orcad 9.1.