I/O modules that convert varying voltage or current to a digital value are known as what type of interface?

I/O modules that convert varying voltage or current signals to a digital value are classified as analog interfaces. This type of interface is designed to process continuous signals, which can vary in amplitude or frequency. The analog interface takes these continuously varying inputs, typically representative of physical phenomena such as temperature, pressure, or flow, and converts them into digital signals that a system can process and understand.

The conversion allows for easier manipulation, storage, and analysis of data in digital systems, facilitating compatibility with digital controllers or microprocessors. This is crucial in instrumentation and control systems where precise measurements and data interpretation are essential for automation and monitoring processes.

The other choices refer to different types of interfaces. Discrete interfaces deal with binary inputs and outputs (on/off signals), digital interfaces handle purely digital signals, and dynamic refers to systems that evolve over time but does not specifically pertain to the conversion of analog to digital signals. Therefore, the classification of I/O modules that convert signals as analog is accurate and aligns with standardized practices in instrumentation.