What makes a good power adapter?

April 14, 2023

How to design a good power adapter?

1, determine your power supply and input voltage. The switching current of the switching tube, transformer volume and input voltage of the switching tube are selected by the power supply.

2, no matter what kind of voltage, power supply, field tube should have low-pass discharge and speed charging circuit.

3, the transformer should have absorption circuit, the harmonic absorption.

4, field tube grid internal resistance should be pulled down with resistance grounding.

5, to choose the appropriate switching frequency, to ensure the minimum static overload loss at the same time, the field tube conversion efficiency is the highest.

6. When the input voltage exceeds 75V, filter resonance circuit should be tested as a negative auxiliary circuit.

7. When the power is too large, it is necessary to test the filter PFC circuit access design.

8, drive signal to be stable! And it has to be more than 5V.

What are the standards for power adapters to be qualified?

In general, the more power adapters have been certified, the more reliable they are. At present, the power supply sold in the market must be sold after the mandatory 3C certification system. The existing 3C certificate has four versions: CCC(S) safety certification, CCC(SE) safety and electromagnetic compatibility certification, CCC(EMC) electromagnetic compatibility certification, and CCC(F) fire protection certification. CCC(S) only means that the safety standard has been passed.

The CCC(S&E) certification standard is in use, which puts forward two requirements on the safety and electromagnetic compatibility of the power supply. If you see the CCC(S&E) mark on the power supply, it can be understood that it has passed the 3C certification, which is also the standard that any power supply product must meet. It does not mean that its quality is excellent. Fake logos are used to fool consumers.

In addition to the 3C certification, the UL certification mark can also be seen on some advanced power supplies. It is one of the current strict certifications, and has related restrictions on the structure, materials, test instruments, and methods of power supplies. Therefore, the general quality of the power supply that has the UL certification mark is guaranteed.

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