Q:Switching power supply, what is the difference between the charger

1, we all know that the electricity is 220V / 50Hz AC, and the computer system components are low-voltage direct current, so the power supply is the protagonist of computer power supply, if the current than blood, then the power is the heart of the computer. After the power into the power, the first through the choke coil and capacitor filter high-frequency clutter and interference signals, followed by rectification and filtering to get high-voltage direct current, and then into the power of the core part of the switch circuit is mainly responsible for DC conversion For the high-frequency pulsating direct current, and then send high-frequency switching transformer buck, and then filter out the high-frequency AC part, so that the computer needs more "pure" low-voltage direct current because the computer power is the core part of the switch circuit, Usually referred to as switching power supply. Turn left to turn right Therefore, the switching power supply is popular on the computer "transformer", the AC power into a fixed DC power supply to the computer components to use.However, the switching power supply and linear power supply is not the same: it first 220V AC change Into the DC, and then through the converter to DC into AC, and finally turn the AC into a DC output. The reason for the conversion to high frequency AC is the high frequency AC in the transformer transformer circuit efficiency is much higher than 50Hz, so the switch Transformers can do very little, and work is not very hot, if not 50Hz into high-frequency switching power supply does not make sense!

Q:Can notebooks have an external switching power supply?

Note: Notebook boot links are different, resulting in different welding, the contact directly on the line, fixed style can also be welded directly, the more troublesome cable, so you need to determine the two contacts are off the switch, you can Try again and again, and then find a point to connect, connect on the line.

Q:What is the difference between an open switching power supply and an ordinary switching power

DC switching power supply, its function is to the power quality of the poor quality of the original ecological power (coarse), such as mains power or battery power, to meet the requirements of the equipment to meet the higher quality DC voltage (fine). DC switching power supply is the core of DC / DC converter. So the DC switching power supply classification is dependent on DC / DC converter classification. In other words, the DC switching power supply classification and DC / DC converter classification is basically the same, DC / DC converter classification is basically DC switching power supply classification. DC DC / DC converter between the input and output whether there is electrical isolation can be divided into two categories: one is isolated as an isolated DC / DC converter; the other is no isolation called non-isolated DC / DC converter.

Q:Hello everyone, I have a switching power supply chip with UC3845, fault: turn on the power instantaneous power indicator light and then off. After the investigation did not find a short circuit phenomenon. When the shortcomings of several consecutive shortcuts on the receiving side of the two pins, the power can be activated. What is the reason for this? thank you all!

Oh, the above two answers I think can not help you solve the problem, because it is not feasible. First of all, according to what you say, you can accurately judge, you are full or overloaded when the normal start. This only shows a reason that the power is instantly activated when the impact is protected. The solution to the problem is to analyze the cause of the problem first. Where the protection is due to power on the moment when the load with the impact of over-current. So the overcurrent protection value should be slightly adjustable to solve. Such as single-ended flyback power supply, can reduce the resistance of the lower end of the MOS tube in order to increase the output over-current protection value, half-bridge or full-bridge circuit, then appropriate to reduce the peak current protection value or output over-current protection value, solved. Many of the output overcurrent or short circuit protection is used in the transformer primary side using the transformer (magnetic or magnetic core) to detect the transformer primary current, to protect the output overload situation. The value of this detected can be appropriately adjusted (the voltage drop resistance value can be appropriately reduced).

Q:Output 12V2A switching power supply, I would like to change to 12V5A, is not the transformer changed on the line

Not to change the transformer, but should be the transformer capacity increases

Q:2014 low-frequency transformer is now the future is ok, the feeling is now doing more switching power supply, the last low-frequency transformer will be replaced

1, low-frequency transformers will not be replaced; 2, low-frequency transformer without switching power supply pulse interference; 3, low-frequency transformer with a variety of power grid pulse interference; 4, low-frequency transformer with switching power supply can not counter the anti-surge ability, especially lightning; 5, low-frequency transformer production of linear power supply has the best introduction of ripple performance; 6, low-frequency transformer output can use low-voltage switch chip, with isolation at the same time also has a high efficiency; In the industry, low-frequency transformers can be a good isolation from a variety of high-power inverter, servo, SCR control caused by interference.

Q:Switching power supply how to repair

You ask too much, can not explain, there are many kinds of switching power supply, fault more, can not explain one by one, and I will only a little bit, generally burn the power to look at the insurance, if not off detection About the film, the visual resistance is not burning, the transformer is generally not bad, the resistance is also less common is the capacitor is broken or the insurance broke, and there are some lightning pressure varistor will burst, useless, just from To protect the role, get rid of it can.

Q:24V switching power supply, 220V input and output three terminals: 24V + 24V- GND. Excuse me. Where is this GND connected? In the PLC (such as Siemens) on the L + M to (ground that symbol) Switching power supply is connected to the ground in the PLC? There are some sensors on the terminal marked with three vertical and horizontal grounding symbol, but also to be connected to the switching power supply on the symbol terminal? What is the relationship between the chassis and the switching power supply on this land? Is it a thing?

You said too messy, I read for a long time, I still use my logical language to tell you! There are some high-end switch, lamp or import switch, the lamp is a ground option. As you said 24V switch, GND should be connected to the switch box or case, assuming that the switch box and the case is non-metallic natural do not have to pick up, the ground is mainly for the metal chassis with electrical appliances, when the fire line leakage On the chassis, the chassis connected to the ground short circuit lead to tripping, play a safe role, so your power must have three lines, that is, line of fire, zero line, ground, your electrical appliances with a ground mark Place to be connected to the power ground, I do not know if you understand, if any questions please continue to ask!

Q:What is the component stress in the switching power supply?

Component stress is the element in the worst working conditions of the environment, for component reliability, the actual consideration of the main voltage stress and thermal stress. General companies set their own derating standards, the use of components in the stress can not exceed the established standards in order to obtain improved reliability.

Q:A DC / DC switching power supply input with UC3843 is a 24V power supply between two power supplies is up to 200M line now the situation is DC / DC power supply at no time when the load is measured at this time DC / DC power input It is actually less than 15V if the DC / DC power supply is loaded with about 10W and the 24V power supply output is adjusted to 27V or more when the DC / DC power supply is working In front of the wrong In the load when the 10W when the front power output is adjusted to 27V measured when the power input voltage is 14.5V or so when the no-load time is normal add another point With 10W when the front of the power output is adjusted to 27V below the two power between the current is significantly increased at this time into the DC / DC power supply voltage from 15V down to 6,7V looks more like the back of the power from Excited and DC / DC of this power supply in the 9V or so input conditions can work properly

There are three problems need to be identified, 1 is the power output power in front of how much, if small, can not be changed, only for the front of the power; 2 is 200 meters diameter, if too thin, a little current Will produce a lot of pressure drop