Design and Analysis of a Multistage Common Emitter Amplifier for Low Frequency Applications

Abstract

The design and analysis of the multistage common emitter (CE) amplifier for improved voltage gain over the single stage CE amplifier is presented in this paper. The design procedure started with the design of a single stage CE amplifier. The design specifications for the CE amplifier were specified. The design of the multistage CE amplifier was done using the designed single stage CE amplifier as the basic configuration. The designed single stage and multistage CE amplifiers were simulated in the linear technology simulation program with integrated circuit emphasis (LT SPICE). The results obtained show that using analytical method a voltage gain of 45 dB was obtained for the single stage and 54 dB was obtained for the multistage respectively, the LT SPICE simulation software presented a result of 44 dB for the single stage and 54 dB for the multistage. The proposed amplifier may find suitable applications in devices operating in the low frequency such as audio signal applications. Furthermore, judging from these results coupling of more stages of the transistor amplifier to obtain greater voltage, current and power gains is recommended.