The Pulse width modulation (PWM) is a method for transmitting information and controlling power using digital square-wave signals. In this method, it is not the amplitude of the signal that is varied, but rather the duration of the on-state (High Level) within a fixed period. The actual information is therefore contained in the pulse width or the duty cycle of the signal.
A PWM signal consists of two switching states High and Low. A complete cycle consists of the duration of the high level and the subsequent duration of the low level. By adjusting the ratio between the on and off times, it is possible, for example, to precisely transmit and control the output power, a control variable, or a setpoint.
In measurement, control, and automation technology, PWM signals are frequently used to efficiently control processes or transmit digital information. Typical applications include motor speed control, valve actuation, LED brightness control, and the output of control signals in test and automation systems.
Of particular importance here are the rising and falling edges of the signal. These signal transitions can be used as trigger or switching pulses in measurement and automation systems. They enable the precise initiation of measurements, synchronization processes, or control functions.
In modern measurement data acquisition and automation solutions from Delphin Technology Digital inputs and outputs can acquire and monitor PWM-based signals or use them for control tasks. This allows measured values and process data to be directly linked to control and automation functions. This is particularly advantageous in test benches, machine monitoring, and research and development applications.
The most important advantages of pulse-width modulation include:
- High precision in the transmission of control and actuator signals
- Energy-Efficient Control of Electrical Loads
- Simple Digital Signal Processing
- High immunity to interference through the use of defined switching states
- Flexible integration into measurement, control, and automation systems
Pulse-width modulation (PWM) is a proven method for digital signal transmission and power control. By varying the pulse width, processes can be precisely controlled, signals can be reliably transmitted, and automation tasks can be efficiently carried out.