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TOOL IDB-SWE-004
ADC resolution

Desktop only

Engineering tools are available only on desktop screens.

ADC resolution & LSB

LSB voltage, ideal SNR, and effective number of bits (ENOB) for an ADC from bits and reference voltage. For sensor front-end design and noise budgets.

Quantization ladder LSB — V
Vref 3.3 V 0 V analog in quantized code 1 LSB — V noise floor 8 of 4096 levels shown
Engineering notes

Formulas

  • LSB = Vref / 2^bits
  • SNR_ideal = 6.02 · N + 1.76 dB
  • ENOB = (SNR_measured − 1.76) / 6.02
  • Noise density: nV/√Hz = V_noise / √(fs/2)

Sanity checks

  • If sensor noise > LSB, you're losing bits — averaging buys about ½ bit per 4× samples.
  • For thermistors 12-bit is usually enough; for strain gauges expect 16-bit minimum.

Result

Live