source:Industry News Popular:adapter release time:2021-06-17 09:48:43 Article author:sznbone
Overvoltage protection technology can be roughly divided into the following three categories
The first category: simple thyristor overvoltage protection.
The second category: Overvoltage protection based on voltage clamping technology.
The third category: Overvoltage protection based on voltage limiting technology.
The selection basis of overvoltage protection technology is: power adapter circuit structure, power adapter performance and cost.
The first category: thyristor overvoltage protection
Just like the meaning of its name, the overvoltage protection can short-circuit the output terminal of the power adapter in response to the output overvoltage of the power adapter. If the output voltage of the power adapter exceeds the preset value within the specified time, then the short-circuit device (Generally, thyristor) will act.
When the thyristor acts, it short-circuits the output of the power adapter, so the output voltage drops. Shown in the figure is a typical thyristor overvoltage protection circuit, which is connected to the output of the linear regulator. When designing a thyristor overvoltage surge protection circuit, it is very important to realize that the bypass function of the product's overvoltage surge protection does not necessarily provide a long-term load protection when the circuit fails.
In addition, the bypass device must have enough power to bear the short-circuit current. For the short-circuit current that exceeds the specified time or the external current limit, a fuse or circuit breaker must be able to function, so as to protect the thyristor from damage.
For linear regulator type DC power adapters, thyristor overvoltage protection is a common method, and the simple application circuit often used is shown in the figure. The working process of linear regulator and overvoltage protection is as follows:
After the unadjusted DC input voltage VH passes through a series transistor Q, the voltage drops, and at the same time provides a lower value but adjusted output voltage V. , The amplifier A1 and the resistors R1 and R2 provide a voltage control for the regulator, and the transistor Q2 and the current-limiting resistor R1 are used for current-limiting protection.
Most catastrophic circuit failures are caused by the short circuit of the series regulator Q1. In this case, the higher unregulated input voltage VH will appear at the output. In this fault situation, the entire circuit loses its voltage control and current limiting functions. At this time, the thyristor, which plays a role of over-voltage protection, must work and short-circuit the output terminal.
Read recommendations:
High quality 47~63Hz dc power supply 12v 6a switching power
5V 3.5A Switching Power Supply Board Module Small Size Bare Board Beauty Equipment Industrial Equipm
Voltage noise improvement method of power adapter,adapter manufacture
The latest article
S series S1000 energy storage mobile power supply
2021-03-18S series S900 energy storage mobile power supply
2021-03-18New ABS Fire Shell Gigabit ESD Protection POE Powered Adapter Power Supply 90W POE Injector
2021-03-18ShenZhen Factory OEM ODM AC DC Open Frame Switching Power Supply Manufacturer
2021-03-18130W bare board power supply
2021-03-1880W bare board power supply
2021-03-1872W bare board power supply
2021-03-1872W bare board power supply
2021-03-1860W bare board power supply (54V)
2021-03-1836W Open Frame Power Supply
2021-03-1836W Open Frame Power Supply
2021-03-1830W Open Frame Power Supply
2021-03-1810W Open Frame Power Supply
2021-03-187W Open Frame Power Supply
2021-03-187W Open Frame Power Supply
2021-03-18Amplifier + power supply
2021-03-1060W single power supply
2021-03-10Amplifier + power supply
2021-03-1027W single power supply
2021-03-10Amplifier + power supply
2021-03-1030W power amplifier power supply
2021-03-10144W power amplifier power supply
2021-03-1048W desktop
2021-03-1048W desktop
2021-03-1024W U.S. regulations
2021-03-1018W U.S. regulations 18W Wall-Mounted Power Adapter
2021-03-1018W U.S. regulations18W Wall-Mounted Power Adapter
2021-03-1018W European standard Power Adapter
2021-03-1018W European standard Power Adapter
2021-03-1018W U.S. regulations18W Wall-Mounted Power Adapter
2021-03-10The latest article
What are the types of mobile phone chargers and their functions?
2022-05-21Advantages of switching power adapters
2022-05-21Five core functions that the power adapter can achieve.adapter manufacture
2022-05-20Analysis of the importance of power adapters for notebooks.adapter Processor
2022-05-20Details of switching power supply in maintenance
2022-05-19Understand the precautions of the power adapter and be an expert in electricity safety
2022-05-19This is how the EMC interference of the switching power supply is generated.adapter wholesaler
2022-05-18The relationship between the nominal voltage and current of the power adapter.power adapter price
2022-05-18Five basic functions of notebook power adapters.adapter wholesaler
2022-05-17Lightning surge immunity test method.power adapter price
2022-05-17Switching power supply ripple source and control
2022-05-16Level 6 energy efficiency standard power adapter T series
2022-05-16Children sleeping with pacifiers are prone to tooth decay
2022-05-16Six methods to deal with the heating problem of switching power supply transformer
2022-05-14The principle of flyback switching power supply
2022-05-14Types of thermal protection for power adapters.adjustable power adapter
2022-05-13Summary of common faults of LED switching power supply
2022-05-13The power transistor should be used like this in the power adapter
2022-05-124 modulation methods of switching power supply
2022-05-12Some little knowledge about switching power supply
2022-05-11Laptop Power Adapter Troubleshooting Steps
2022-05-119 classification methods of switching power supply
2022-05-10Advantages and disadvantages of switching power supply current mode
2022-05-10Advantages and disadvantages of switching power supply current mode
2022-05-099 classification methods of switching power supply
2022-05-09Characteristics and working methods of PFC regulated switching power supply
2022-05-07Six maintenance rules for drone lithium batteries.manual charger power adapter
2022-05-07Reasons for Inrush Current in Switching Power Supply Design.adjustable power adapter
2022-05-06The optimal solution of drone power management solution!12w acdc power adapter
2022-05-06Characteristics of Switching Power Adapter Transient Loads
2022-05-05About
Product
Process
News
Recruitment
中文
Online consultation
Online map
中
