An analog input module converts analog signals to digital values using an A/D converter.

• A. True
• B. False
• C. It uses D/A converters
• D. It uses PWM

Answer: (A)

Analog input modules read a real-world signal and turn it into a digital value that the PLC can process. This is done with an A/D converter, which samples the incoming analog voltage or current and quantizes it into discrete digital levels based on the module’s resolution. That’s exactly what the statement describes, so it’s correct. Using a D/A converter would do the opposite—convert digital values back into analog signals—and PWM is a modulation method used to create variable outputs or approximate analog levels, not to convert an input signal to digital form.