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Arduino Based Voltmeter
The voltage ‘V2’ is a fraction of the actual applied voltage ‘V’. The applied voltage ‘V’ can be calculated from the fraction of applied voltage ‘V2’ with the help of the following equation. DC voltage, Vdc = V2 * (1 + (R1 / R2)) AC voltage as input: When we are applying an AC voltage we use a rectifier diode in series with the Voltage divider circuit to prevent the negative cycles from entering the circuitry. No need for step down transformers because we are already getting a voltage ‘V2’ in the range of 0 to 5 V only, across R2.
Arduino Based Voltmeter