home > News > Industry News

The structure and characteristics of linear power adapter

source:Industry News     Popular:adapter     release time:2020-12-16 18:16:56     Article author:sznbone    

The switching power supply is different from the linear power adapter. The former regulator tube works in the on and off state, and the latter regulator tube works in the linear state. The power adapter realizes voltage stabilization by controlling the on and off time of the regulator tube. The advantages of the power adapter are small size, light weight, low power consumption, wide voltage regulation range, and efficiency up to 80% to 90%. The power loss of the regulator tube is small, and the radiator is also reduced accordingly. The operating frequency of the British standard power adapter is tens of kilohertz or even hundreds of kilohertz. The filter inductance and capacitance components can be used with a smaller capacity, and the allowable ambient temperature can also be greatly increased. It is widely used in various electronic devices. This chapter mainly introduces the basic composition, classification and working principle of the power adapter, so that readers have a preliminary understanding of the power adapter.

Comparison of regulated power adapter

Electronic equipment cannot do without power adapter. The power adapter supplies the energy required by the electronic equipment. The performance and quality of power adapters directly affect the safe and reliable operation of electronic devices, so the requirements for the performance and quality of power adapters for electronic devices are getting higher and higher. There are two main types of existing power adapters: series linear regulated power adapters (referred to as linear power adapters) and switching regulated power adapters (referred to as power adapters). These two types of power adapters have their own characteristics and are widely used.

 

The structure and characteristics of linear power adapter

The block diagram and output waveform of the linear power adapter are shown in the figure.

 

Figure Linear power adapter block diagram and output waveform

Linear power adapters are usually obtained from AC power provided by the power grid through transformation, rectification, filtering and stabilization. The functions of each part of the circuit are as follows:

①The power adapter transformer-converts the 220V grid voltage into the AC voltage required by the rectifier circuit, and a small number of circuits use capacitors to step down, such as remote-control electric fan circuits.

② Rectifier circuit-convert AC voltage into pulsating DC voltage. Commonly used rectifier circuits include half-wave rectifier circuits, full-wave rectifier circuits and bridge rectifier circuits.

③Filter circuit-converts the pulsating DC voltage into a smoother DC voltage. The filter circuits commonly used in linear power adapters include inductance filter, capacitor filter and resistance-capacitance filter. The most commonly used one is capacitor filter.

④Stabilizing circuit-stabilize the output voltage of the DC power adapter, basically not affected by the grid voltage or load. The voltage stabilizing circuits commonly used in linear power adapters include diode stabilization and series stabilization. Among them, there are ready-made integrated circuits for series voltage stabilization, such as fixed voltage output integrated circuits such as LM78××, LM79××, etc., and adjustable voltage output integrated circuits such as LM317 and LM337.

The picture shows a linear stabilized power supply adapter with 4 functional modules including mains voltage step-down, rectification, filtering and voltage stabilization.

 

 

 

Linear regulated power adapter with 4 functional modules

 

The advantages of the linear power adapter are good stability, fast transient response, high reliability, high output voltage accuracy and low output ripple voltage; the disadvantage is the low operating frequency, the volume and weight of the power frequency transformer and filter used Both are larger. The adjustment tube works in a linear state, has high power consumption and low efficiency, and requires an additional radiator. In general, the efficiency of the linear power adapter will not exceed 50%, but its excellent output characteristics,


Read recommendations:

40W 4USB Charger,40W Charger,4USB Charger

MKD-571202000 ADAPTER AC ADAPTER CE ADAPTOR UL ADAPTOR Linear Adapter

ER42 High Frequency Transformer

Slow charging? Try a fast charger

The requirements must pay attention to Plug-in power adapter apply for UL1310 Class 2 unit

Related Information

What are the conditions of use and maintenance methods for switching power supplies?

2022-05-21

Some Frequently Asked Questions about Power Adapters

2022-05-20

How to deal with the electromagnetic interference of switching power supply which is difficult in EM

2022-05-19

Six situations and solutions that cause the whistling of switching power supplies.power supply price

2022-05-18

Lightning Surge Test Method for Switching Power Adapters.adapter factory

2022-05-17

Two common power adapter output overload protection methods.ADAPTOR price

2022-05-16

Common fault maintenance skills of switching power supply

2022-05-14

How should we choose the charger?

2022-05-13

Power adapter expertise.CE ADAPTOR

2022-05-12

How to solve the high temperature rise of switching power supply transformer?

2022-05-11

The role of varistor in switching power supply

2022-05-10

Structural characteristics and working principle of varistor

2022-05-09

The role of varistor in switching power supply

2022-05-09

What are the main components of switching power supply

2022-05-07

Two ways for MOS devices to dissipate in high-power power supplies,CE ADAPTOR Processing

2022-05-06

Several common insulation protection technologies for power adapters

2022-05-05

What are the unique advantages of high frequency switching power adapter

2022-04-27

What are the main components of switching power supply.China cnc plastic cutting

2022-04-26

Troubleshooting method of switching power supply,CE ADAPTOR wholesale

2022-04-25

How to use the power adapter correctly

2022-04-23

What is the comparison between a charger and an adapter?

2022-04-23

The optimal solution of drone power management solution!

2022-04-22

Several common insulation protection technologies for power adapters

2022-04-21

What are the unique advantages of high frequency switching power adapter

2022-04-20

General Mechanism Analysis of Switching Power Adapter.ac power adapter wholesaler

2022-04-19

Suppression method of low frequency ripple of switching power supply

2022-04-16

Why is the power adapter making noise?

2022-04-15

When the power adapter is in normal use, what is the normal temperature?

2022-04-14

90% of people use the car charger incorrectly, are you using it right?CAR POWER SUPPLY sales

2022-04-13

The difference between a power adapter and a voltage regulator

2022-04-12

Popular recommended products

24-36W Charger,36W Charger,24W Charger,30W Charger

2020-08-27

12-24W Medical Switching Power Supply

2020-08-27

MKS-1203000EX Switching Power Supply

2020-08-29

45W PD Charger,45W Charger,PD Charger

2020-08-27

MKS-120200EU-36 Switching Power Supply

2020-08-29

MKA-571652420 ADAPTER AC ADAPTER CE ADAPTOR UL ADAPTOR Linear Adapter

2020-08-28

MKS-1202000-36 Switching Power Supply

2020-08-29

EI-66 ADAPTER LINEAR ADAPTOR SWITCHING ADAPTOR Linear Power Adapter Linear Adapter

2020-08-28

12W CAR CHARGER,12W USB CAR CHARGER,CAR CHARGER,12W CHARGER

2020-08-27

MKS-120200BS-36 Switching Power Supply

2020-08-29

12W 2USB Charger,2USB Charger,12W Charger,USB Charger

2020-08-27

EI-48 ADAPTER LINEAR ADAPTOR Switching Power Adapter INTERCHANGEABLE ADAPTOR Linear Adapter

2020-08-28

30-500W LED Power Supply 30-500W Power Supply

2020-08-27

24-65W Switching Power Supply

2020-08-29

12W POWER SUPPLY,12W CAR POWER SUPPLY,POWER SUPPLY,CAR POWER SUPPLY

2020-08-27

100-300W Charger,100W Charger,200W Charger,300W Charger

2020-08-27

24V1.5A 36W Switching Power Supply

2020-08-29

EI-57 ADAPTER LINEAR ADAPTOR Linear Power Adapter Switching Power Adapter INTERCHANGEABLE ADAPTOR Li

2020-08-28

3-15W Switching Power Supply

2020-08-28

19V2A 36W Switching Power Supply

2020-08-28

MKD-571202000 ADAPTER AC ADAPTER CE ADAPTOR UL ADAPTOR Linear Adapter

2020-08-28

12VDC8A 96W power supply

2020-08-28

40W 4USB Charger,40W Charger,4USB Charger

2020-08-27

EI-35 ADAPTER AC ADAPTER SWITCHING ADAPTOR Linear Power Adapter Linear Adapter

2020-08-28

EI Power Transformer Power Transformer

2020-08-27

EI-41 ADAPTER AC ADAPTER LINEAR ADAPTOR SWITCHING ADAPTOR Linear Adapter

2020-08-28

18-25W Switching Power Supply

2020-08-28

24-65W Medical Switching Power Supply

2020-08-27

24W 2USB Charger,24W Charger ,2USB Charger

2020-08-27

12-36W POE POWER SUPPLY

2020-08-27
Copyright 2020 © Merryking Technology Co., Ltd. All rights reserved