International Journal of Modern Science and Technology


ISSN 2456-0235

​​​​​​​April 2019, Vol. 4, No. 4, pp 97-100. 

​​Design of Multistage Amplifier for Small Signal Audio Applications

S. Muthukumar, M. Arunraj*, D. Deepa, P. Rajesh, A. Santhiya
Department of Electronics and Communication Engineering, Adithya Institute of Technology, Coimbatore, India.

​​*Corresponding author’s e-mail:


The proposed multistage amplifier can be used in audio applications. It is designed by using cascade connection with BJT and FET. The multistage amplifier has only one input that is ac signal (sin wave) and output is audio signal. The amplifier is working at a resonance frequency of 1 KHz to 3 Mhz and it is designed by using pspice software. The proposed amplifier hardware setup is done by breadboard. The gain of the multistage amplifier is very low and the frequency is maintaining constant at particular level (31.16 gain).

Keywords: Field effect transistor; Bipolar junction transistor; Common source circuit; Common emitter circuit.


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