ADC Resolution Calculator Formula

Understand the math behind the adc resolution calculator. Each variable explained with a worked example.

Use the ADC Resolution Calculator

Formulas Used

LSB Size

lsb_mv = v_ref / pow(2, bits) * 1000

Quantization Levels

num_levels = pow(2, bits)

Dynamic Range

dynamic_range_db = 20 * log10(pow(2, bits))

Variables

VariableDescriptionDefault
bitsADC Bits(bits)12
v_refReference Voltage(V)3.3

How It Works

ADC Resolution

Formulas

LSB = V_ref / 2^N

Levels = 2^N

Dynamic Range = 20 x log10(2^N) dB

N is the number of bits. Each additional bit doubles the resolution and adds 6 dB of dynamic range.

Worked Example

12-bit ADC with 3.3 V reference.

bits = 12v_ref = 3.3
  1. 01Levels = 2^12 = 4096
  2. 02LSB = 3.3 / 4096 = 0.000806 V = 0.806 mV
  3. 03Dynamic range = 20 x log10(4096) = 72.2 dB

Ready to run the numbers?

Open ADC Resolution Calculator