A Study on Port Protection and Alarm Circuit of Microcontroller Training Kit

Abstract

Background/Objectives: In this paper, we propose a circuit that protects the port of the microcontroller training kit from the overvoltage input by the mistake of the trainee and warns the trainee of this situation.

Methods/Statistical analysis: In order to analyze the functions that the protection circuit should have, we analyze the frequent cases of user mistakes and compare the existing methods to defend them.The analysis showed that the overvoltage components flowing into the microcontroller training kit had to be discharged from the protection circuit itself and a means of informing the user was necessary.

Findings: Based on this analysis, we proposed a circuit that can generate the alarm signal while protecting the port of the training kit.This is based on the constant voltage by NFB(Negative Feed-back) of operational amplifier, and it is used as alarm signal by using control voltage of operational amplifier. To verify the effect of the proposed circuit, an experimental circuit was constructed and the experiment was conducted.

Improvements/Applications: As a result, it was confirmed that the port signal exceeding the normal range was discharged by itself and the signal informing of this situation was generated. 

Keywords: Microcontroller, Training, Education, Protection, Alarm, Overvoltage, Detection