Purpose of A/D Conversion
2 Answers
In industrial control processes, it serves as an indispensable interface between control systems and microcomputers. To achieve automatic control, it is necessary to detect relevant parameters. The A/D converter transforms the detected voltage or current signals (analog quantities) into equivalent digital quantities that computers can recognize. These digital quantities are processed by the computer, and the output results are converted back into voltage or current signals through a D/A converter, which are then sent to actuators to achieve the purpose of controlling certain processes. Analog-to-Digital (A/D) Conversion: Converts analog signals into digital information, primarily used for digital acquisition of analog signals. The most common example is digital cameras. Additionally, it is frequently employed in digital measurements such as voltage, current, speed measurements, etc. Digital-to-Analog (D/A) Conversion: Converts digital signals into analog signals, mainly used for transforming output signals and control signals from digital mode to analog mode. Examples include VGA output for computer display signals and control of certain digital automation equipment.
I reckon this issue is like asking why we need a translator in a car. Sensors like the engine temperature sensor and throttle position sensor actually measure continuously varying analog signals such as voltage and current, but the engine control unit (ECU) only understands digital signals. The job of the A/D converter is to 'translate' these analog signals into 0s and 1s so the computer can comprehend them. Without this conversion, the ECU would be completely blind—knock detection, precise fuel injection, all of it would fail. Imagine if the air-fuel ratio control error exceeds 5%, the engine starts misfiring—it's all thanks to this real-time conversion that enables precise control. If you add a turbo to a modified car but ignore signal conversion accuracy, the fuel injection goes haywire, and you could end up with a blown engine in no time.
