DAC Output Voltage Calculator

Work out dac output voltage instantly with clear inputs, formula shown and shareable results.

About DAC Output Voltage Calculator

A DAC's output is code times the LSB size, where LSB is Vref divided by 2^n. Note that full scale is one LSB below Vref, since the maximum code is 2^n - 1 — a detail that matters when calibrating a converter against its reference.

Formula

DAC transfer

Vout = code x Vref / 2^n; LSB = Vref / 2^n

Worked example

With the default values below, DAC Output Voltage Calculator returns Output voltage of 1.650000. Change any input above and every figure here is recalculated in your browser.

Inputs used

DAC resolution: 12 bits
Reference voltage: 3.3 V
Input code: 2,048 counts

Results

Output voltage: 1.650000 V
LSB step size: 0.81 mV
Full scale output: 3.29919 V
Percentage of full scale: 50.000% %

Step by step

1Values used
2DAC transfer
3Output voltage= 1.650000 V
4LSB step size= 0.81 mV
5Full scale output= 3.29919 V
6Percentage of full scale= 50.000 %

Assumptions and limits

The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 6 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

Why is full scale not exactly Vref?

Because the code range is 0 to 2^n - 1. The top code gives Vref x (2^n - 1)/2^n, one LSB short of the reference.

What sets real accuracy?

Reference accuracy and drift, plus the DAC's own integral and differential non-linearity. A 12-bit DAC with a 1% reference is only about 7 bits accurate in absolute terms.