ADC Bit Resolution Calculator

Introduction

This tool computes the voltage resolution or the smallest voltage that can be measured by an analog-to-digital converter (ADC).

Every ADC is the number of bits it uses to digitize samples of the analog input. An n bit ADC produces 2ⁿ discrete digital levels.

The larger the number n, the higher the resolution.

Enter:

• Number of bits
• Maximum Analog Input Voltage
• Minimum Analog Output Voltage

ADC Resolution Formula

An ADC accepts an analog voltage at its input and converts it to an n-bit digital value. A 12-bit ADC for instance produces 2¹² = 4096 discrete values at its output.

The analog resolution or the smallest value that can be measured by the ADC is given by the formula:

(V_max – V_min)/2ⁿ

where

• V_max is the maximum input voltage
• V_min is the minimum input voltage
• n is the number of ADC bits

The difference between V_max and V_min is the input voltage range

Calculation Example

A 12 bit ADC with an input voltage range of 3.3 Volt has a resolution of 0.81 mV.

Increasing the number of bits, increases the ADC resolution and therefore the precision of the measurement.

? A related concept is the Quantization Error of the ADC.

ADC Resolution Table

The following shows the ADC resolution for an input voltage range of 5V

Related Calculators

• ADC SNR
• Sampling Rate
• DAC Resolution
• Bipolar ADC
• ADC Effective Resolution