Arduino Voltmeter using SH1106 OLED display
A voltmeter is an important tool on the workbench of every electronics hobbyist, maker or hardware design engineer. As it’s name suggests, allows the user to measure the voltage difference between two points. For today’s tutorial, we will look on how you can build an Arduino based DIY voltmeter, for use in situations where you don’t have the standard meters around.
Measuring a DC voltage, should probably be as easy as connecting the voltage to be measured to an analog pin on the Arduino, but this becomes complicated when voltages are higher than the Arduino’s operational voltage (5V). When applied to an analog pin, Arduino will not only give false reading but it could also damage the board. To solve this, today’s project uses the principle of voltage divider such that only a fraction of the voltage to be measured is applied to the Arduino. This fraction of voltage that goes in is determined by the ratio of the resistors used, as such, there is usually a limit to the maximum voltage that can be applied. For this tutorial, we will use a combo of a 100k and 10k resistor, with the 10k resistor on the “output side”. Feel free to experiment with other resistor values as well.
Arduino Voltmeter using SH1106 OLED display – [Link]