In the era of technology evolving to fulfill our interests, sometimes we find a limitation in personalizing our applicants as per our needs. These personalizations can be due to our needs to ensure less energy loss or more efficiency or customized outcomes per our interest.
From the four basic methods of modulation naming: Analog modulation, Digital modulation, pulse modulation, and spread spectrum method, pulse modulation is convenient for sending analog information in the form of pulses.
Pulse width modulations are easy to take control over devices like a microcontroller. It sends pure analog signals from a digital controlling device to other devices. These signals form a pulse-like waveform with a high point and low point.
What is Pulse Width Modulation?
Pulse width modulation is a control technique used in various electronic devices, especially performing on AC/DC motors. It is a modulation process that encrypts analog signals from a device that controls its performance.
Sometimes changing the lights, sound, or speed of a device can be tough for everyone. Altering the voltage of the power supply can help, but it is not easy enough to conduct. So here comes PWM (Pulse Width Modulation) in rescue.
Instead of changing the voltage of the power supply, Pulse width modulation emits some square analog signals that constantly make the device on and off, which occurs at such a speed that it appears to be in a constant power supply with an actual voltage.
Applications of Pulse Width Modulation
- PWM circuits are often used in modern LED bulbs to control their brightness.
- PWM can generate maximum torque even at the lowest speed, for which it is used in modern-day vehicles.
- PWM methods can eliminate noise from the signal, so it’s used in telecommunication.
- Motherboards of smartphones and computers consist of PWM circuits to decrease heat radiation.
Advantages of PWM
Less power consumption
PWM works by repeatedly making the device on and off, by which minimal power is lost. As a result, it requires less power to perform and conserves energy. Using PWM can be a sustainable approach toward energy conservation.
To create pulse width modulation, we require a pulse width modulation circuit that will emit a signal using 555 times that will constantly turn on and off the power MOSFET transistor, giving control to change its performance as per requirement. This circuit doesn’t come with a cost burden.
Though PWM doesn’t work on a specific alteration of the voltage of the power supply, it works more efficiently than those devices which require a specific voltage to change its outcome. It is 90% more efficient than the other 3 prominent modulations.
The LED bulbs with PWM work more efficiently and change their brightness more conveniently than other light bulbs.
It is not affected by the high power supply.
PWM consumes low power to work upon. Still, a high power supply doesn’t change its performance level. Unlike other modulations, PWM has a high power handling capacity.
PWM eliminates noise more efficiently and has less noise interference. It sends the analog signal in a lengthy wireline, minimizing noise interference and distortion.
Moreover, it has an inherent immunity against noise interruptions due to its constant amplitude. This is the reason PWM is mainly used in modern telecommunication devices.
Produces more torque
PWM motors can produce more torque even at lower speeds which helps the motor generate more power to rotate the axis. This is very efficient for vehicles requiring more power.
Generates less heat
PWM circuit works on less energy which generates comparatively less amount of heat. Therefore, when energy is lost in heat in other circuits, PWM works more efficiently by losing less energy.
Independent control of amplitude and frequency
The main advantage of PWM circuits is that they can independently control the amplitude and frequency of the waveforms.
Synchronization between transmitter and receiver is not needed.
Unlike pulse position modulation, where synchronization between transmitter and receiver is essential, PWM doesn’t require any specific sync.
Can separate signal from noise
Received pulse can be easily separated from noise by cutting off the amplitude as per requirement, which also does not affect the signal, which stays in the width of the pulse.
Disadvantage of PWM
The making and working process of a pulse width modulation is certainly complex. In addition, it requires a semiconductor with low on and off frequency, which can also cost a lot.
Frequent voltage spikes
Voltage spikes are generally expected in PWM circuits. However, these voltage spikes can create unnecessary interruption and gradually damage the fuse.
Communication requires a large bandwidth
Unlike the bandwidth of pulse amplitude modulation (PAM), a large bandwidth is required in PWM to transmit signals in communication mediums. In addition, large bandwidths can store more signals than smaller ones, so small bandwidth pulses are more likely to acquire noise inference.
If the transmitters used in PWM are in the same or similar frequency, they are very likely to get Radio frequency interference. It can disrupt the signals and corrupt the message in the communication medium.
In PWM, the pulse width is variable, each having different power contents. A lower power transmitter can be affected by pulse width containing high power. To avoid problems with the transmitter, a powerful transmitter is required.
The power of a pulse depends on its width. In PWM, width varies from signal to signal so that the power will remain variable.
From the electric LED light bulb to vehicles used for transportation, Pulse width modulation has been proven to be an effective modulation method. However, beyond the facts that show the limitations of Pulse width modulation, we can consider it a call for a modern sustainable method where it works more efficiently in a low-cost modulating system.
Pulse width modulation allows personalizing the devices as per our needs. Which also consumes less power and works more steadily without unnecessary interference.