ADC Resolution Visualizer

ADC Resolution Visualizer

Watch nominal ADC bits become useful sensor resolution, then trade averaging time for lower independent noise

Interactive ADC resolution visualizer for ADC count width, quantization, RMS noise, ideal averaging, ENOB, acquisition time, and sensor sensitivity.

Interactive animation ADC fundamentals

ADC Resolution Visualizer

Watch a smooth sensor voltage move through sample-and-hold, quantization bins, and a digital code register. Then see how independent noise reduces useful bits and how averaging buys resolution by spending acquisition time.

8-bitSelected resolution

12.89 mVVoltage per count

430Current code

Setup

See how analog voltage becomes discrete digital codes.

Try

Choose “12-bit noisy LM35”, then change only Average count from 1 to 64.

Observe

Useful bits rise from 9.19 to 11.6 while acquisition time rises from 1.00 ms to 64.0 ms.

Explain

Nominal bits set ideal count width; noise, averaging, and sensor sensitivity set useful resolution.

ADC Setup

Scenario preset Teaching demo Teaching demo - 8-bit, 3.3 V Arduino Uno - 10-bit, 5.0 V ESP32 - 12-bit, 3.3 V Raspberry Pi Pico - 12-bit, 3.3 V nRF52840 - 14-bit, 3.6 V ADS1115 external - 16-bit, 4.096 V 12-bit noisy LM35 - misconception test

Resolution 10 bits

Unipolar input span 5.00 V

Manual Sample Voltage 2.10 V

Noise magnitude 2.00 count RMS

Average count M = 1 12481632641282565121024

Sample rate (log scale) 1000 sample/s

Sensitivity (log scale) 0.0100 V/deg C

Sensor Scenario LM35 temperature sensor Soil moisture analog probe Battery voltage monitor Position knob

Live Numbers

Levels

1,024

Step Size

4.88 mV

Digital Code

430

Binary

0110101110

Error Band

+/-2.44 mV

Useful bits (ENOB)

9.19 bit

Effective interval

5.64 mV

Smallest quantity

0.564 deg C

Acquisition time

1.00 ms

Analog to Digital Conversion Animation

The moving cursor samples the analog wave. The ADC maps that sample into one code bin and emits the digital code shown below.

Sample

1. Analog sensorSmooth voltage changes continuously.

2. Sample holdA moment in time is captured.

3. QuantizerThe voltage lands inside a bin.

4. Digital codeThe bin becomes a binary number.

sample

0 V2.50 V5.00 V

analog voltage quantized ADC output current sample quantization error RMS-equivalent uncertainty band

Digital code register

OK

Fit for coarse monitoring

This setup can show about 0.49 C per count for the selected temperature sensor.

A 12-bit ADC does not always resolve twelve useful bits.Independent noise leaves 9.19 useful bits at M = 1.

Learning Support

Beginner Model

Bits create bins. An 8-bit ADC has 256 bins, a 10-bit ADC has 1024 bins, and a 12-bit ADC has 4096 bins across the reference voltage.

Design Rule

Your ADC step should be smaller than the smallest useful sensor change. Extra bits do not help if sensor noise is larger than the step.

What to Notice

• More bits make the staircase finer.
• Lower reference voltage also makes each step smaller.
• Noise can make extra bits unusable.

Quick Reference

Bits	Levels	3.3 V Step	5 V Step	Typical Fit

Technical Notes

Code Width

This teaching model uses LSB = Vref / 2^N and code range 0 to 2^N - 1 for an ideal unipolar ADC.

Quantization Error

The orange band is input +/- sqrt(3) sigma_total: an RMS-equivalent band whose half-width equals one effective quantization interval. It is not a confidence interval.

Noise-Limited Fit

Find Minimum now includes the selected noise-count estimate, so it does not recommend more bits while ignoring a noisy sensor path.

Technical boundaries. This is an ideal unipolar ADC plus independent RMS noise and ideal uncorrelated averaging. It does not simulate offset, gain error, DNL/INL, missing codes, aperture jitter, reference drift, aliasing, correlated or 1/f noise, sensor nonlinearity, calibration, or saturation outside the selected span. Averaging improves only the independent-noise term; it cannot recover biased or correlated measurements.

Microchip ADC code width Microchip quantization error Analog Devices ADC basics