Ripple and noise

This is a feature page about ripple and noise in switching power supplies for AC/DC power adapters — desktop & wall-mount. It provides basic knowledge about ripple and noise, and explains their relation to AC/DC power adapters — desktop & wall-mount. Please feel free to contact us if you have any questions.

"Ripple" and "Noise" are among the performance indicators of AC/DC Power Adapters — Desktop & Wall-Mount, and our specifications state them as follows. (Excerpt from Unifive product specifications)

Both "Ripple" and "Noise" represent small fluctuations included in the DC output voltage, which ideally should be zero. However, due to the nature of the technology, it is difficult to eliminate them completely. Therefore, the smaller these fluctuations, the better the performance of the AC/DC Power Adapters — Desktop & Wall-Mount.

That said, just because they are smaller does not necessarily mean it is a "better AC/DC Power Adapters — Desktop & Wall-Mount". Minimizing "Ripple" and "Noise" affects the number and size of components used, which in turn increases the size, weight, and cost.

Therefore, it is important to choose an "AC/DC Power Adapters — Desktop & Wall-Mount" with optimized performance for your equipment.

Now, regarding the differences between "Ripple" and "Noise", they are defined in the standards of the Japan Electronics and Information Technology Industries Association (JEITA) as shown in the diagram below.

(Excerpt from the JEITA standards)

"Ripple" refers to fluctuations consisting of frequency components at 50/60Hz from the AC power source, while "Noise" refers to fluctuations consisting of frequency components above several tens of kHz caused by switching in the AC/DC Power Adapters — Desktop & Wall-Mount. The combination of both is called "Ripple and Noise", and the relationship is: "Ripple", "Noise" < "Ripple and Noise" < "Ripple" + "Noise".

We provide a variety of AC/DC Power Adapters — Desktop & Wall-Mount suited to different applications. Individual specifications can be downloaded, so please take a look. We also specialize in custom solutions. If you have any questions, feel free to contact us. We are here to respond to your "I wish this existed..." needs.

The JEITA standards introduced in this article can be purchased from the page below. Some documents can also be viewed for free, so please check there for details.

JEITA Standards > General Electronic Components Division > Conversion Components <DC Stabilized Power Supply>

Related content