Abstract—A small-signal amplifier with three identical MOSFETs in Darlington’s topology is proposed and qualitatively analyzed perhaps for the first time. Unlike CSMOSFET amplifiers, the voltage gain of the proposed circuit is found considerably higher than unity. This amplifier can be used to amplify audio range signal excursions swinging in 0.1- 2mV range. In the narrow-band performance range, the proposed amplifier produces simultaneously high voltage and current gains with low harmonic distortion. These properties offer a flexible application range to the proposed circuit as high-voltage-narrow-band amplifier in permissible audiofrequency range. An additional biasing resistance RA is to be essentially used in the proposed circuit to maintain its voltage/current amplification property. Variations in voltage gain as a function of frequency and different biasing resistances, temperature dependency of performance parameters like voltage gain, bandwidth, current gain, input/output noises and total harmonic distortion of the amplifier are perused to provide a wide
Index Terms—Small signal RC coupled amplifiers, darlington amplifiers, common Source MOS amplifiers, triple darlington amplifiers, MOSFET darlington pairs.
Sachchida Nand Shukla, Senior member IACSIT, is with the Department of Physics and Electronics of Dr. Ram Manohar Lohia Avadh University, Faizabad-224001, U.P., India (e-mail: firstname.lastname@example.org)
Susmrita Srivastava is with the Department of Physics and Electronics of Dr. Ram Manohar Lohia Avadh University, Faizabad - 224001, U.P., India(e-mail: susmrita @rediffmail.com)
Cite:Sachchida Nand Shukla and Susmrita Srivastava, "A New Circuit Model of Small-Signal Amplifier Using MOSFETs in Triple Darlington Topology," International Journal of Modeling and Optimization vol. 3, no. 5, pp. 394-398, 2013.