Embedded Systems

ADC Voltage Measurement Guide

Learn how ADC resolution, reference voltage and scaling affect voltage measurements.

How ADC conversion works

An ADC converts analog voltage into a digital number.

Formula

A common formula is V = Code / (2^N - 1) × Vref.

Resolution

A 10-bit ADC has 1024 possible codes. A 12-bit ADC has 4096 codes.

Voltage dividers

When measuring voltage above the reference, a voltage divider or amplifier stage is often required.

Design notes

ADC accuracy depends on reference stability, source impedance, noise and PCB layout.

Use the calculator

Try the related tool and calculate your own values instantly.

Open ADC Voltage Calculator