Analog-Digital-Converter

Home  ⇒  Overview Courses   ⇒  Digital Electronics  ⇒ ADC

Analog-Digital-Converter

Analog-to-digital converter (ADC) in parallel or Flash-ADC 

An Analog-to-Digital Converter (ADC) in parallel, also known as Flash-ADC, consists of a comparator stage and an encoder stage, which must be a priority encoder. The comparator stage consists of several individual comparators, the exact number of which depends on the resolution (number of bits) of the ADC.

The number of comparators required can be calculated by

Number = 2^n - 1, where n is the number of bits to be represented.

For the 3-bit ADC shown below, we therefore need 2³ - 1 = 7 comparators. For a more common 8-bit ADC, 255 comparators would be required.