What is an Analog-to-Digital Converter (ADC)
The ADC converters translate analog electrical signals, usually the voltage amplitude, into a sequence of discrete values (integer number) for data processing purposes. The bit resolution of the analog to digital conversion determines the magnitude of the quantization error. The number of discrete levels depends on the number of ADC bit resolution. For an N-bit ADC, the number of discrete possible values is 2^N.
For example, for 8-bit ADC the input signal is discretized in 2^8=256 different values.
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