18-01-2012, 03:53 PM
Analog to Digital Conversion
(5)ADC.ppt (Size: 2.62 MB / Downloads: 137)
Why ADC ?
Digital Signal Processing is more popular
Easy to implement, modify, …
Low cost
Data from real world are typically Analog
Needs conversion system
from raw measurements to digital data
Consists of
-Amplifier, Filters
-Sample and Hold Circuit, Multiplexer
- ADC
Terminologies
Converter Resolution
The smallest change required in the analog input of an ADC to change its output code by one level
Converter Accuracy
The difference between the actual input voltage and the full-scale weighted equivalent of the binary output code
Successive Approximation ADC
Most Commonly used in medium to high speed Converters
Based on approximating the input signal with binary code and then successively revising this approximation until best approximation is achieved
SAR(Successive Approximation Register) holds the current binary value