Differences Between Linear and Switching AC/DC Power Converters

Differences Between Linear and Switching AC/DC Power Converters

Choosing the right energy source is vital for running a system. You can choose between switching and linear power supplies for your electronics. Each power source has its positive and negative sides. You must understand the differences between linear and switching AC/DC Power Converters.

What are linear power sources?

Linear power sources have no high-frequency switching and ensure a low-noise solution. You can choose them for applications that need low ripples and strong regulations. Moreover, the linear power source is the right choice when you need minimal electromagnetic emission. This power supply depends on a transformer to reduce voltage from the AC line. It then conducts the filtering process and uses rectifier circuitry to generate a good DC voltage.

The most common applications of linear power supply are-

  • Medical equipment
  • Communication tools
  • Signal processing
  • Low-noise amplifiers
  • Sensors
  • A/D converters
  • Lab test equipment
  • Automatic test equipment

Know about switching mode power supply

Switching power sources have a unique design to deal with most issues (like voltage regulation and transformer size) related to linear power supplies. The design of the switching power supply does not reduce the input voltage. After flowing through a chopper, the voltage converts it into high-frequency pulse trains. This leads to reduced parts sizes. That is why modern devices are compact and small.

Switching power supplies is different from the linear ones because the former ensures rectification before regulating voltage. The rectified current needs a switching device, and the low-frequency AC is converted into a high-frequency wave.

The high-frequency rectified current works as the pseudo-AC that enters the transformer, depending on the load requirements. It leads to a filtered output, and voltage is controlled with the response from the output.

With a compact design, switching power sources are more efficient than the linear ones. Thus, they are best for applications that need extreme efficiency. You can use them as the power source for your

  • Smartphone
  • Servers
  • Computers
  • LED lights

There are also devices integrated with switching power supplies. However, you need external power supply products for other gadgets.

Linear power supplies

Pros:

  • Minimal noise and comparatively low output ripple
  • A simple design with a few basic components
  • More reliable and easier to repair.
  • Cost-effective- Perfect for lower power requirements.

Cons:

  • The linear power sources do not have high efficiency.
  • There is a risk of heat generation
  • Power supply voltage control is not very precise
  • Lower power output

Switching power supplies

Pros:

  • A low-cost solution for your high-power application
  • Highly efficient and ensures minimal heat dissipation
  • Higher power output- Needed for bigger applications

Cons:

  • This leads to more noise.
  • Costly for low-power applications

Comparing linear switching power sources

The major differences between these power sources are the power supply size and the noise level. The switching power source turns on and off the switch repeatedly at a significant speed. It can produce noise because of switching. On the contrary, a linear power supply generates minimal noise. The height is the same for both the power sources. However, the linear power supply system is comparatively wider and deeper.

The switching power source produces an output regulated by a circuit. But, with your linear power source, the regulator circuit’s response will control the output. So, you will get a faster response from the switching power supply converters.

The linear power supply generates more heat. When your device consumes more power, you must take measures to reduce the heat emitted.

This is a comparative analysis of linear and switching power supply converters. You can compare them thoroughly and make the right choice.

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