AC DC ADAPTER What is an AC DC adapter?

Related Vendors

ROHM Semiconductor GmbH

Rogers Corporation

SPACE SE & Co. KG

Electronic devices such as phones, laptops, computers, and home appliances cannot generate electricity but draw power from an external source. An AC/DC adapter is an intermediate stage that provides AC power from the mains “continuously” to all these devices. The article explains AC/DC adapters in detail.

The name “AC/DC adapter” points out the device’s function of converting AC to DC. As you already know, a device that converts AC to DC is a rectifier. AC/DC adapters also contain an inbuilt rectifier for power conversion. These are commonly used chargers for laptops and computers.

What is an AC DC adapter?

An AC/DC adapter is a device that converts high-voltage alternating current (AC) from a wall outlet into stable direct current (DC) and delivers it to all the connected devices. The DC current at a stable low-voltage level enables the connected device to operate constantly. An AC DC adapter can keep the client device in operation, preventing it from turning off. In addition, AC/DC adapters are commonly used to charge devices up to their maximum battery capacity.

What is an etl certified ac power adapter?

Every electronic device sold in the market has to be tested for safety. Certifications by regulatory authorities ensure device safety for consumers and the environment. In the world of AC/DC adapters, ETL certification is an abbreviation for “Edison Testing Laboratories”. Intertek, a Nationally Recognized Testing Laboratory (NRTL), issues this certification. ETL is a standard certification in North America, including countries like the USA, Canada, and Mexico.

An ETL-certified AC DC power adapter is a safety and performance standard-compliant. The certification ensures that each AC DC power adapter meets quality, consumer, and environmental safety standards with high electrical performance. Such power adapters are safe to use and are resistant to shock and fire. As a result, the ETL mark enables the safe use of chargers in homes and offices.

KEYNOTE PCIM EUROPE 2022

From state of the art to future development trends of power supply

What does an AC DC adapter do?

The internal structure of an AC DC power adapter consists of a step-down transformer, a bridge rectifier, and a filter. The step-down transformer steps down the high AC voltage level to a lower AC voltage level. The rectifier performs the rectification operation— converts AC to DC. The rectifier can either be half-wave or full-wave type.

The output of the rectifier can be a pulsating DC or contains AC components. A filter is placed at the rectifier output. Once the rectifier shows a DC output, the filter smoothes out the DC waveform to eliminate unwanted noise. In most cases, a reservoir capacitor is used as a filter. As a result, the output of an AC/DC adapter is a stable DC voltage.

AC-DC Conversion

Modern electronic devices lack internal components to draw voltage and power from the main switch. Hence, an AC/DC adapter functions like an intermediary device that doesn’t generate electricity but draws power from the main switch and delivers it to these devices. In simple terms, AC DC power adapters are AC-to-DC converters.

Voltage transformation

An AC/DC adapter performs the voltage transformation operation, typically voltage step-down. Depending upon the country of operation, an AC DC adapter obtains 240 V or 120 V from the mains. It steps down the voltage to another voltage level. For example, a laptop may use 12 V DC. The other electrical appliance may use 5.5 V DC. A device or its battery can operate safely on a low-voltage/current, compared to challenging high-voltage or current operation.

DIRECT CURRENT

What's the difference between AC-DC and DC-DC power supplies?

What are AC DC adapters used for?

When the power supply is constant, only a connected device can fully operate or the battery can charge. Alternating current comes and goes in cycles. A device cannot remain on or the battery cannot fully charge from 0 to 100 % in the AC power supply. It makes DC necessary for device operation and battery charging. As a result, AC DC adapters enable seamless charging in electronic devices.

When should I use an AC DC adapter?

You should use an AC DC power adapter with compatible devices that have DC power input in the charging slot. The voltage, current, and power requirements and ratings of the device should match the AC/DC adapter type.

Fans, refrigerators, ovens, TVs, washing machines, and many more high-power home appliances need AC power to function. In such cases, the AC/DC adapter is not applicable for use.

Choosing the right AC DC power adapter?

Choosing the right AC/DC adapter depends upon connector type, device requirements, ratings, choice of the manufacturer, and certifications. Efficiency is a typical indicator of a good quality AC DC power adapter. The efficiency ranges from 80 PLUS Bronze (lowest) to 80 PLUS Titanium (highest about 94 %). Some popular names in the market have released their AC DC adapters. Some of the features have been described below:

• XP Power AC DC Power supplies: The certified AC DC power adapters in the series are known for their repeatability, ease of integration, low noise, and EMC compatibility. VCE05 series have wide input and single output capabilities for industrial applications.

• Motorola wall chargers: Motorola, also known as Galvin Manufacturing Corporation in the 1920s, was the very first manufacturer of AC DC power adapters.

• TDK-Lambda Americas medical grade chargers: The company manufactured a wide range of commercial AC/DC adapters for industrial and high-power applications.

• ETA-USA customized chargers: ETA-USA manufacturers offer AC DC power adapters and DC-DC power supplies for military, aviation, and medical equipment. There are customized AC DC adapter solutions for industrial applications.

• Mean Well GST series: The name Mean Well is well-known for its LED components, inverters, adapters, and battery chargers. Mean Well GST series is a popular laptop charger series.

• Samsung wall chargers: South Korean giant Samsung offers AC DC wall chargers for laptops, smartphones, and cars. However, they are mostly sold with the respective devices.

• Targus universal chargers: Targus, a London-based company, offers a variety of electronic products— including a universal all-in-one solution to charge laptops. The universal charger is compatible with major Windows OS-based laptops.

References

• https://energyeducation.ca/encyclopedia/AC_adapter

• https://www.lenovo.com/in/en/glossary/ac-adapter/?orgRef=https%253A%252F%252Fwww.google.com%252F&srsltid=AfmBOopLRyY63Mts82iRbBleRHtL1ynOxJR2KOfPlmw8vp9ARqOqBmcg

• https://www.mpofcinci.com/blog/what-is-etl-certification/

Power Electronics in the Energy Transition

The parameters for energy transition and climate protection solutions span education, research, industry, and society. In the new episode of "Sound On. Power On.", Frank Osterwald of the Society for Energy and Climate Protection Schleswig‐Holstein talks about the holistic guidance his organization can provide.

Listen now!

(ID:50261649)