Analog To Digital

Analog to Digital Conversion (ADC) is the process of transforming continuous analog signals, which can have an infinite range of values, into a digital format that computers and digital devices can interpret. This conversion is essential because most electronic devices operate using digital signals.

Analog To Digital ©2025 Eric Wells Hatheway

The ADC process involves several key steps:

1. Sampling: This step involves measuring the amplitude of the analog signal at regular intervals. The frequency of sampling is crucial and must be at least twice the highest frequency present in the analog signal, according to the Nyquist theorem, to accurately capture the signal without losing information.
2. Quantization: After sampling, the continuous range of the analog signal’s amplitude is divided into discrete levels. Each sample is assigned the nearest value within these levels, which introduces a small error known as quantization error.
3. Encoding: Finally, each quantized value is converted into a binary code, which represents the digital output. This binary code can then be processed, stored, or transmitted by digital systems.

ADC is widely used in various applications, such as audio and video recording, digital photography, telecommunications, and medical devices. The quality of an ADC depends on its resolution (number of bits used to represent each sample) and its sampling rate, both of which affect the accuracy and fidelity of the converted digital signal.