SMPS Full Form

SMPS also known as switcher stands for switched mode power supply. It is an electronic power supply device which acts as a switching regulator and converts electric power. The SMPS converts a DC to AC in some cases like an AC adapter or converts AC sources to DC in some cases like computers or laptops. It also converts both current and voltage characteristics. Unlike other power supplies the transistor of SMPS continuously works between full on and off in low power dissipation mode. It also takes very little time for high power dissipation transition which in turn minimizes the energy wastage. Actually an ideal SMPS wastes no energy. It works on switching frequencies ranging from few kilohertz to few megahertz, where typical AC main frequency ranges between 50 and 60 hertz. These regulators are mainly used to replace the linear power regulator where the requirements are higher efficiency, lighter weight or smaller size. However, they also have some issues to deal with such as electrical noise problems if they are not properly suppressed, also they have pretty complex designs. Those having simpler circuits more often have very poor performance.  

The idea of SMPS was originated in 1972 by Hewlett Packard. He designed it to use for the pocket calculator but later on seeing its potential as a power supply he changed the main design and SMPS was officially patented in 1976.

Importance in daily life

In the era of technology and computers it is necessary to have a regulated power supply which will work in accordance with our supply needs, and will not waste too much energy like other regulators. SMPS comes just in time to serve for that. It’s smaller size and weight also comes handy while decorating or organizing any device which is using it. 

Advantages

1) The main advantage of using SMPS is its efficiency. Where other power supply devices or PSUs give efficiency about 60 to 70 percent it has an average efficiency between 80 and 90 percent.

2) Unlike other heavier and large sized regulators it has a unique small size and is lightweight. This helps to design and decorate devices more compactly. 

3) It generates very low heat. It actually takes less time to convert high power supply resulting in low energy waste. And hence low electric cost. 

4) It takes a low frequency input, rectifies and filters it and converts the voltage using a high frequency converter and then again it rectifies and filters the output. This reduces the harmonic feedback into the main supply. 

5) It has a very low manufacturing cost, and is also very easy to repair. 

6) One of the main characteristics of SMPS is that it can provide a number of different voltages as per the device’s need. 

Disadvantages

1. The main disadvantage of it is its complex circuit. Expert design is needed to manufacture UT. There are few SMPS available in the market having much easier circuits, but to do so their efficiency and power factor is greatly compromised. 
2. Its other main problem is that it gives only one output, so it can’t be used in multiple devices. 
3. When it works as a high frequency switch, much to our annoyance, high frequency noise arises. However, this problem can be easily solved using a separate rectifier, but this would obviously hamper its Compactness. 
4. It also produces harmonic distortion which can be caused in heating computer, desktops using it. 
5. Sometimes electromagnetic interference occurs while using it, creating a humming sound in the regulator. 

Comparison

We can compare between two main types of power supply regulator available in market that is SMPS and line regulator using some basic features as follows 

1. Energy loss: SMPS has lesser energy consumption or loss than the linear power supply. 
2. Complexity : SMPS circuit is much more complicated than the linear one.
3. Electric noise in output:  SMPS is much noisier. If the output is not filtered it can cause glitches or create noises. 
4. Electric noise in input : in linear one harmonic distortion is relatively low, but the problem with SMPS can be reduced using EMI or RFI filter between input and bridge rectifier.

Applications

It is commonly used as a low voltage power source for lights and often called ‘electronic transformers’. It is also used in automobiles. 

Precaution

The capacitor of the CR filter sometimes stores a huge voltage up to 325 volts and if anyone touches this capacitor, it will give massive electric shock. 

Conclusion

Like every other electronic device it also has its own pros and cons. It can sometimes come in handy as well as can cause annoyance. We will have to consider this before choosing what to use and what to not. If your priorities are compactness, efficiency then SMPS would be your go-to option. The problems it has can also be dealt with easily but it would cost the main advantages to some extent. Overall it is a great device to have if someone is using computers, desktops or laptops.