Analog signals typically are not ADC friendly, but they can be with some relatively simple circuitry such as a low pass filter and amplifier. The goal is to have the analog signal cover the entire range of the ADC. For example, if your input goes from 0V to 1V and your ADC measures from 0V to 3V, you will need to amplify the input to take full advantage of the ADC. Voltage scaling seems easy enough but you also need to make sure the frequencies you are measuring are low enough for your sample rate which is where filtering comes in.
Analyzing Op Amps
Operational amplifiers, or op-amps as they are affectionately known, are very useful when designing embedded systems and relatively easy-to-use. If you know just a few of the basics, you can design and analyze op-amps like a boss.
Sensing the Source Current in an Embedded Application
This is a simple, low-cost way to measure the current output at the power source of an embedded system using a microcontroller’s ADC input.