Hardware Secrets has posted an article how analog-to-digital converter (ADC) works
Signals in the real world are analog: light, sound, you name it. So, real-world signals must be converted into digital, using a circuit called ADC (Analog-to-Digital Converter), before they can be manipulated by digital equipment. In this tutorial we will give an in-depth explanation about analog-to-digital conversion yet keeping a very easy to follow language.How Analog-to-Digital Converter (ADC) Works
