Ac Dc adapters: (2022) Everything you should fully understand

The AC DC adapters have many advantages, so it is so widely used. There are many people who confuse the role of AC DC adapters and batteries. In fact, the two are fundamentally different. The battery is used to reserve power, and the AC DC adapters is a conversion system that converts the current and voltage that is not suitable for the device into the current and voltage suitable for the device to the battery.

If there are no AC DC adapters, once the voltage is unstable, our computers, notebooks, TVs, etc. will be destroyed. Therefore, having an AC DC adapters is good protection for our household appliances, and also improves the safety performance of the appliances. In addition to improving the safety performance of electrical appliances, it is the protection of our own bodies. If our electrical appliances do not have power adapters, once the current is too large and suddenly interrupted, it may cause electrical explosions, sparks, etc., resulting in explosions. Or fire, which is a great threat to our life and health. It can be said that having an AC DC adapters is equivalent to insuring our household appliances. Never worry about those accidents again.

pacolipower ac-dc-adapter

What is an ac dc adapters?

AC DC adapters, also known as external power supply/DC Charger/AC DC Charger/ DC Supply, are generally used as power supply voltage conversion equipment for small portable electronic equipment and electronic equipment. It is usually used in small electronic products such as mobile phones, LCD monitors and laptops etc. The function of AC DC adapters is to convert the high voltage of 220 volts from the household into a stable low voltage of about 5 volts to 20 volts that these electronic products can work with so that they can work properly.

Application of ac dc adapters

When we initially recognize the role of ac dc adapters, then I believe many people will also have a question what is an ac dc adapters used for?

 ac to dc adapters can be used in many industries, such as: industrial automation control, scientific research equipment, industrial control equipment, communication equipment, power equipment, semiconductor refrigeration and heating, air purifiers, electronic refrigerators, communication equipment, audio-visual products, In the fields of computer cases, digital products, etc., the devices that need power supply are currently inseparable from the power adapter.

Guidelines for power adapters with different parameters

Are all AC-DC adapters the same?

In fact, each AC DC adapters has two distinctions in appearance. One is wall adapters and desktop adapters. This is the fastest way for ordinary people to distinguish AC DC adapters.

However, the parameters of AC DC adapters used on different devices are very different, so in this guide, we will list some industries that use adapters most often and the specific parameters that the device will use.

Communications industry

High reliability, high temperature, lightning protection, and large voltage fluctuations. The power supply system used by the central office equipment is generally 48V output; various base station amplifiers generally use 3.3V, 5V, 12V, 28V ac dc adapters, 3.3V, 5V ac dc adapters generally have chips, 12V adapter fans, and 28V adapter output power amplifiers.


Generally, there are many output channels. To prevent mutual interference between groups, the ac dc adapters require high voltage regulation accuracy, and some need to be isolated. (Some of the input voltage is DC, and the frequency of the ship or aircraft is 440HZ.) Some instruments, such as oxygen generators, hydrogen generators, etc., also require a constant current power supply, and the leakage current is very low.

Security industry

Generally used with battery charging, such as 12V adapter /13.8V adapter, 13.8V ac dc adapters are generally charged with battery, and switch to 12V battery for power supply after AC power failure.

Network fiber

Network switches generally use 3.3V adapter/5V adapter and 3.3V adapter/12V adapter in many combinations. 3.3V adapter generally has a chip, and the power varies according to different types. The voltage regulation accuracy is high, 5V ac dc adapters, 12Vac dc adapters with Fan, the current is very small, and the voltage regulation accuracy does not need to be very high.

Medical industry

It has higher requirements for safety, requires small leakage current, and high withstand voltage. Usually the ac dc adapters used are 12V-120V depending on the device.

LED display industry

The requirements for ac dc adapters are: good dynamic response, high temperature resistance, and some may require a large overcurrent point, such as 5V30A adapters, 5V50A adapters power supply, LED decoration, because of the lighting requirements, it basically needs constant flow to achieve a uniform luminous brightness.

Tax control industry

Emerging industries are controlled by the government, and the production volume may be very large. Except for a few, basically use 5V 24V combined with ac dc adapters, 5V for the main chip, 24V with printer, and need to cooperate with the whole machine to do EMC.

Set top box

Generally, there are many channels, the typical voltage is 3.3V adapters/5V adapters/12V adapters/22V adapters/30V adapters, or some ATX standards, the current of each channel is very small, and the total power of ac dc adapters is generally about 20W, and the price is lower. Some set-top boxes with hard drives will have more than 60W of power.


Usually, there are more than 3 channels of 24V adapters/12V adapters/5V adapters, 24V with LCD screen; 12V with the audio system; 5V with TV control board and STB.

Switching power supply

New industries involved: audio and video equipment, battery cabinet charging equipment, VOIP communication terminal equipment, power modulation and demodulation equipment, non-contact identification equipment, etc.

How do I know what size ac dc adapters I need?

The parameters of ac dc adapters will vary according to different devices, so it is not possible to use ac dc adapters for charging at will. Before choosing ac to dc adapters, three adaptation conditions must first be determined.

1. The Power Jack/Connector of the ac dc adapters matches the device;

ac dc Power Jack matching

2. The output voltage of ac dc adapters must be the same as the rated input voltage of the load (mobile device), or within the voltage range that the load (mobile device) can withstand, otherwise, the load (mobile device) may be burned;

AC DC adapter current pairing device

3. The output current of ac dc adapters should be equal to or greater than the current of the load (mobile device) to provide sufficient power;

What makes a good ac dc adapters?

When we have learned about the application of AC DC adapters, we should also know how to choose good AC DC adapters. A good adapter can help your project achieve great success

Reliability of DC adapters

According to the main performance of ac dc adapters, such as overcurrent protection, EMI radiation source, working voltage offset, harmonic distortion suppression, cross-loading, clock frequency, dynamic detection, etc., it is determined whether the power adapter can run smoothly for a long time.

The convenience of DC adapters

Convenience is one of the first elements that everyone must take into account. Electronic equipment is gradually developing in the direction of small and exquisite. Of course, the same is true of ac dc adapters. In order to better carry it, you must consider choosing AC to DC Adapters on a lightweight computer.

Environmental protection and energy saving of DC adapters

The key to ac dc adapters is high conversion efficiency. The high conversion efficiency of the switching power supply at the beginning was only 60%. Now it can achieve more than 70% and a better 80%. BTW, this is also proportional to the price.

Compatibility mode of DC adapters

Because ac dc adapters do not have a unified standard interface, the current equipment on the market can be said to be different at the connector level. Everyone should check carefully when choosing. ac dc adapters usually have a floating value of working voltage and ac dc adapters with similar voltages. It is compatible with applications, as long as it does not exceed the larger scope of electronic equipment.

Durability of DC adapters

If you find that adapters are damaged before you use them, then I believe many people will feel distressed because of this, because the durability of ac dc adapters is relatively critical because of the natural environment of the application. In addition to the normal application of connection voltage and electronic products, many people often take ac dc adapters around, some stumbling is inevitable, and the cable will often break, which confirms that its aging rate is getting faster , the service life is not so high.

The structure of the ac dc adapters

Among them, the DC-DC converter is used for power conversion, which is the core part of ac dc adapters. In addition, there are circuits such as startup, overcurrent and overvoltage protection, and noise filtering. The output sampling circuit (R1R2) detects the output voltage change and compares it with the reference. Voltage U, the comparison error voltage is amplified and pulse width modulation (PWM) circuit, and then the duty cycle of the power device is controlled by the drive circuit, so as to achieve the purpose of adjusting the output voltage.

DC-DC converters have a variety of circuit forms, commonly used are PWM converters whose working waveform is a square wave and resonant converters whose working waveform is a quasi-sine wave.

For a series linear regulated power supply, the transient response characteristics of the output to the input are mainly determined by the frequency characteristics of the pass tube. However, for the quasi-sine wave resonant converter, for the switching regulated power supply, the transient change of the input is more manifested at the output end. While increasing the switching frequency, the transient response problem of ac dc adapters can also be improved due to the improved frequency characteristics of the feedback amplifier. The transient response of load changes is mainly determined by the characteristics of the LC filter at the output end, so the transient response characteristics can be improved by increasing the switching frequency and reducing the LC product of the output filter.

Where To Buy Ac Dc adapters?

We hope this guide to ac dc adapters explained the basic makeup of these chargers and how to size the right ac dc adapters for your application. We also explain how to differentiate between good and bad ac dc adapters and how to pair the right ac dc adapters with your device.

Now is the time to source the right type of ac dc adapters for your application. Here at Pacolipower we bring an abundance of ac dc adapters to manufacture. Our wide range of products and low prices for ac dc adapters make us the supplier of choice for most projects.

Ac Dc adapters: Everything you should fully understand

Post time: Aug-05-2022