Měřicí platforma -- jednoduchý operační zesilovač

Abstract

This bachelor’s thesis deals with the analysis of the internal structure of an operational amplifier and the design of its discrete implementation using bipolar junction transistors (BJTs). The theoretical part describes the fundamental building blocks of operational amplifiers, in particular the differential input stage, current mirrors, voltage gain stage, and output stage, including their operating principles and their influence on the overall amplifier performance.

In the practical part, a custom operational amplifier is designed using discrete components. The design allows switching between passive and active loads in selected parts of the circuit and compensation using Miller capacitance. This enables analysis of the influence of individual design modifications on the dynamic behavior of the amplifier.

The functionality of the proposed circuit is verified using the LTspice simulation tool. The main focus is on the analysis of the frequency response for different circuit configurations. Key parameters such as voltage gain, bandwidth, and stability are evaluated.

The thesis contributes to understanding of operational amplifier design principles at the discrete component level and demonstrates the impact of load selection and compensation techniques on the resulting frequency characteristics.