Interfacing Voltage Sensor with Arduino

The Interfacing Voltage Sensor with Arduino project centers around measuring external DC voltages safely using an Arduino Uno. Because the Arduino Uno's analog-to-digital converter (ADC) can only read voltages between 0V and 5V, attempting to measure higher voltages directly would damage the board. To solve this, the voltage sensor module employs a resistive voltage divider circuit. This network of resistors steps down the incoming external voltage—up to a maximum of 25V—into a proportional, lower voltage range that falls comfortably below the 5V threshold of the Arduino's analog input pin. When you connect the sensor to the Arduino Uno using jumper wires, the module outputs this scaled-down analog signal. The Arduino's built-in ADC then samples this analog voltage and converts it into a digital value ranging from 0 to 1023. By using the Arduino IDE, you can write a simple program to read this digital value, apply the inverse mathematical formula of the voltage divider ratio, and translate the data back into the actual external voltage being measured. Finally, using a digital multimeter allows you to cross-verify the readings displayed by your code against physical measurements, ensuring your circuit is operating accurately and reliably.