TABLE OF CONTENTS Bonnie Baker
The analog-to-digital converter (ADC) is always in the back seat of the station wagon, looking at the analog signal through the rear window. In a way, I am soft on this device because this is the position I was at in my family's station wagon throughout my childhood, being one of six children.
The controller, in the front seat, can see the results of the converter's labor, but the question is, can those results be counted on? If the ADC reports the system data incorrectly, the controller is blind to errors that have been introduced by the converter and signal chain. This is true unless you are willing to allocate a lot of code to try to unscramble the mess (with no guarantee of success). But why not go to the source of the problem? Believe me when I say that the ADC can cause you a great deal of heartache if you don't understand the nuances. Your misunderstanding of how to use the ADC can leave the controller or processor struggling with erroneous or inaccurate data.
In this chapter, we are going to discuss the key specifications for ADCs and how they can impact the expected results from your converter. This list of specifications generally applies to all classes of converters. Then we will delve into the particulars of the Successive Approximation Register (SAR) ADC. This part of the discussion will start with an explanation about how the SAR converter works. The issues discussed...
