RMS measurement error vs ADC bit count.

Analogue to Digital Converter (ADC) – Bit Count Superstition

Analogue to Digital Converters (ADC) convert real world signals into binary code.

A common misconception with ADCs is that the bit count is a key indicator of accuracy in a digital measurement. This leads to the notion that a higher bit count is the result of a more accurate instrument.

There are a number of factors that affect overall system performance, from the quality and condition of the analogue signal to the conversion and even the mathematical post-processing conducted on the result.

In the whitepaper Analogue to Digital Converter (ADC) – Bit Count Superstition, Newtons 4th (N4L) analyse:

  • The features of ADC, like balance of performance and Effective number of Bits (ENOB).
  • Bits required for Root Mean Square (RMS) measurements, simulation sampling & quantisation, low-ranged signals and bit loss.
  • Hardware ranging and signal conditioning, superimposed signals and the International Electrotechnical Commission (IEC) standard.
  • Waveforms, their analysis and the RMS of complex waveforms.

Using detailed examples, N4L look at modern power analysers and their role in optimising the performance of ADCs. Read the whitepaper Analogue to Digital Converter (ADC) – Bit Count Superstition. [664k PDF]


Caltest Instruments Ltd.Designing an accurate measurement system requires expert insights into the balance and consideration of multiple components.

Caltest Instruments are experts in the field of power instrumentation. Call us on 01483 302 700 and speak with our experts to create a system that’s ideal for your power project.