Design voltage regulator for a power supply

Abstract

There are many electronics courses have covered the topics about the linear voltage regulators. Even though the contents are useful, learners may not be given much time to build the circuit to investigate the performance and behavior of the important components, the component characteristic and the theory of parts in the regulator. During the experiment time, many of the learners just build up a power supply using a ready-made voltage regulator and conduct testing, record the measurement results, finally get the conclusion of the output voltage with the changing line and load voltage or current. With these, people miss the chances to know the actual process and working principles on how the different elements of the regulator make effects to the regulator performance. This project is to discover the inside of the series voltage regulator and to address some issues in a common linear voltage regulator. In this project, the characteristic of the major component in a single voltage regulator will be introduced. A DC-DC series regulator (12V to 9V) will be built and some protection circuit will be added for further protection of the voltage regulator circuit. An electronic software named as iCircuit is used to simulate the regulator circuit for the whole project. The results shown in the software is under ideal condition but it clearly emphasizes the circuit function and support the theory behind. Each individual circuit of the circuit was simulated to get the expected results. Attempts were made to simulate the whole circuit, however, there are differences between simulation and the actual circuit testing results, these are due to the component tolerance. Therefore there are changes during the testing and expected results were achieved.