source:Industry News Popular:adapter release time:2021-05-11 11:17:20 Article author:sznbone
Switching power supply with 12V use widely in life, such as monitoring camera, security protection, router, ADSL, interchanger, LCD monitor, LED lamp, portable DVD, speaker, etc. So, how to solve the problem when 12V switching power supply not work?
Fuse burning
Checking big filter capacitor, rectifier bridge and switching tube which above 300V, problem with anti-jamming circuit also causes fuse burning and become black. Attention that fuse burning causes by switching tube strike will burn current sense resistor and power supply controller.Negative termperature coefficient thermistor is easy to burn together with fuse.
SMPS no output, fuse ok
This describes SMPS doesn’t work or be protective. Firstly, test the starting point of the power controller and see if there is starting voltage. If no starting voltage or it is too low, then check the starting resistance and the component disjunctive to tarting point and see if there is electric leakage. If the power controller works noamal, it can find the problem asap after the above check. If there is starting voltage, checking the output of the controller and see if there is high or low change, if no, it obviously know that the controller broken, outer ascillating circuit or protective circuit with problem. Under this circumstance, change the controller, and check the outer components; if there is jump, it is normally switching tube broken.
There is output voltage but higher enough
This is from stabilibolt sampling and voltage stability control circuit. DC output, resistance sampling, error sampling amplifier such as TL431, optocoupler, switching controller and other circuits form a close contol loop, any problem will cause output voltage rise.
Output voltage lower enough
Except for the voltage stability control circuit which causes low voltage, below reasons also cause low voltage:
1. There is short trouble with the switching power supply(especially DC/DC converter short circuit or performance poor), at this moment, all loads should be switched off, so that to distinguish the problem with SMPS circuit or load circuit. If voltage output ok when switch off load circuit, it causes by overload; if not work, it is problem with SMPS circuit.
2. Switching transformer not work not only cause output voltage drop, but also cause switching tube damage.
3. Judge through method of substitution for the failure of output voltage of commutation diode and filter capacitor.
4. Performance reduction of switching tube must lead to the normal breakover of switching tube, enhance the internal resistance of SMPS, reduce the load capacity.
5. 300V filter capacitance failure leads to a poor load capacity, the output voltage will be reduced once loading.
Read recommendations:
power adapter AC 90v-264v input to DC 12V for CCTV LED strip, Router and more
Low Power12v 3a variable adjustable dc power supply for sound equipment
Types of overvoltage protection
What are the internal structure of the power adapter.ac power adapter Factory
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
