Why does my phone charger get very hot? Why does the charger get hot when charging the phone? Methods for eliminating overheating
Of course, any charger during its operation must warm up at least a little; here it is enough to recall the Joule-Lenz law, which indicates to us that if current flows through a conductor, then heating of this conductor will also be observed, if, of course, we are talking about a real conductor, for example a copper one, or a semiconductor from which diodes and transistors are made.
Even the most ordinary wires, one way or another, always warm up a little due to the current. But some chargers sometimes get extremely hot. Let's try to figure out why this happens.
In the case of current chargers, the reason for their heating or overheating is not only Joule heat. Any modern mains charger is, first of all, . And in a step-down pulse converter there is, firstly, a ferrite pulse transformer or at least a ferrite choke.
You probably won’t see iron transformers in chargers today. Secondly, pulse converters have field-effect transistors and, thirdly, rectifier diodes. Thus, there are as many as three sources of heating here.
Ferrite core
At the input of a typical charger there is a voltage that converts the AC mains voltage into direct voltage. This constant voltage of about 300-310 volts is supplied in short pulses to a pulse transformer or to a choke (depending on the charger circuitry), which contains a ferrite core.
So, pulses with a frequency of several tens of kilohertz are applied to this inductive element. The core of the inductive element is real, which means that when it is magnetized and demagnetized, eddy currents arise in it one way or another, not to mention saturation. So, during the operation of the charger, this ferrite core heats up.
And if the developer of the charger tried to make it as compact as possible, then the core probably selected and installed the minimum possible size for a given power, while increasing the frequency of the converter. As a result, the core, of course, overheats.
If, for example, the normal frequency for the core is 50 kHz, and all 250 kHz is applied to it. The size turned out to be smaller, but in return more heat will be released, because ferrites, capable of reversing magnetization at high frequencies without overheating, are more expensive, and the size, again, will be larger, which is not beneficial for marketing.
Transistor
A transistor (field-effect or bipolar) converts the rectified mains voltage into high-frequency pulses that are supplied. This is how most chargers are designed. In rare cases, there may be two transistors. If the charger is relatively powerful, then the transistor needs a heat sink to remove heat, because the transistor heats up according to the Joule-Lenz law.
If the manufacturer of the power supply decided to save on the size of the radiator, or did not install it at all, or even installed cheap transistors with high channel resistance, then the device, of course, will overheat. This happens quite often in non-original chargers.
Rectifier diodes
Rectifiers, which convert low pulse voltage into constant low voltage for charging, are located at the output and also heat up. They have a voltage drop of 0.2 (at best) to 0.5 volts, and with an output current of, say, 1 ampere, some noticeable amount of heat will already be generated only on these diodes. And if the output current is greater, and if the voltage is less, this greatly affects the efficiency.
Conclusion
Thus, if you want your charger to heat up as little as possible and not overheat, buy original (from the manufacturer of the device being charged) chargers that have high-quality components installed, where the developer did not try to save on everything, but focused on the quality of his product.
Yes, almost all chargers get hot. There's nothing wrong with that. But to be on the safe side, it’s better not to leave the charger on while you’re away. Here, some people advise turning off the phone while charging, then the charger will not get too hot. Yes, this method really helps. I checked it personally.
If the charger gets slightly warm during operation, there is nothing to worry about. This is fine. Put your hand on the ventilation grille of your TV, or touch the bottom of your laptop; they all generate heat while functioning.
Another thing is if the charger heats up and becomes almost hot. In this case, it is advisable to disassemble it and check whether everything is in order, nothing is leaking, and there are no foreign odors.
In addition, when charging the phone, under no circumstances should it be placed under a pillow or covered with anything. The heat generated by the device must escape freely.
This can happen due to a faulty charger (contacts burn out) or the socket in which the charger is plugged in is not entirely suitable for it: the device dangles and, as a result, heats up.
I'm talking about situations when the charger gets hot significantly.
Chargers for modern smart assistants: laptop, tablet, smartphone, regular mobile phone, GPS navigator... are electrical circuits through which current flows.
Without going into the nuances of converting alternating current (mains) into direct current (for charging) and without dwelling on the elemental base, it should be noted that the electric current itself passing in the conductor leads to an increase in internal energy and its heating.
The law connecting the amount of heat generated with current and resistance was discovered by scientists J. Joule and E. Lenz.
It is written like this:
Q is the amount of heat,
I is the magnitude of the electric current,
R - circuit resistance,
t — time.
8th grade physics does not describe all the reasons why the charger heats up. Of course, it is necessary to take into account electromagnetic processes in the transformer (its efficiency) and other points. But the Joule-Lenz law works.
You can learn more about heating conductors from this video tutorial
There is no need to worry, but you need to remember some physical properties of electric current. It is known that every conductor of electric current has resistance. Roughly speaking, electrons must be pushed between the atoms of the conductor, collide with them, and heat is released, which heats the conductors. Therefore, the power supply temperature of 50 - 60 degrees is quite normal. It should be noted that all the parts are in a plastic case, which transfers heat very poorly to the environment.
It's okay. Now everything is small and everything gets hot, this is in the order of things, but of course you need to know when to stop. When I bought myself a phone and put it on charge for the first time (while clicking it), I couldn’t hold my finger on the charger for a long time.
I'll tell you from my own experience. I have an extension cord for 3 sockets, not a surge protector, I bought it on ozon ru, and two devices are connected to it - a table lamp and a computer, and when I connect the charger to the third free socket, it heats up quickly, but when I just connect it directly to the wall outlet - then charging is normal. Hence the conclusion - the quality of the socket is also affected by the load on the socket.
Almost all phones still have this particular drawback. While the phone is charging, there is a load on the charger. According to the diagram, there is a transformer and a diode bridge, which create a closed circuit when the phone is connected, and this circuit heats up, that is, the transformer mainly heats up, but this does not change the matter. And how many times have I noticed that (sometimes you forget to unplug the charger from the network) nothing like this happens if the phone is turned off. The charger is practically cold.
To charge the phone, a small voltage is used, and the network, as you know, has an alternating current of 220 V. In the process of transforming electricity, some energy is inevitably lost in the form of heat, but it happens that charging the phone gets too hot. This is exactly the case that will be discussed in this article.
Contents
Should the charger get hot?
If you purchased a certified charger for a specific phone model, then the electricity converter should not heat up greatly. At normal ambient temperatures, the device may operate with a slight increase in temperature, but this condition of the device is not critical.
Strong heating of the charger case may indicate problems with the device itself or with the phone being charged. This electronic condition is abnormal and must be corrected.
What can overheating of the charger lead to?
At a minimum, operating the device in overheating mode can lead to failure of the main charging elements. Components such as electrolytic capacitors and transistors should not be operated at too high temperatures. If the charger constantly operates in this mode, then rapid failure of the device is possible.
If the board is damaged and a short circuit occurs, high currents can cause a fire. Even if a fire does not break out, the plastic casing may melt, which can cause an electric shock when trying to unplug the device or a severe thermal burn from the melted plastic.
Why does the charger get hot?
There can be quite a few reasons for the charger becoming very hot. A similar phenomenon can be observed both for natural reasons and as a result of a memory failure.
Natural causes
The charger may heat up due to natural reasons. Regardless of the power, any device of this type has an efficiency of less than 100%, so energy losses during the conversion of electric current will occur with the release of heat.
If the smartphone supports fast charging, then when this mode is activated, charging can also get quite hot. This effect occurs due to the supply of higher current to the battery contacts.
Due to malfunctions
Most often, charging gets hot due to incorrect selection of diodes at the stage of design and production of the product. If the adapter is assembled in China, then this is not surprising, because the quality of products supplied from this Asian country leaves much to be desired.
If the charger is heated from the moment of purchase and warms up to the temperature of a heating radiator operating in winter, then this may also indicate that it is working at the limit of its capabilities. This situation can occur when operating a working device to which too high a load was connected.
How to understand what the problem is
To find the cause of excessive heat, you should look at the charger label. If the specified value in mA is less than what is required to charge the battery of a particular phone model, then such a device will always work with the release of a large amount of thermal energy.
If the charger is covered with any object during charging, the product body may also become very hot. In this case, the charger may burn out due to overheating.
A short circuit in the charger, cable or phone connector will also cause the device to become very hot. It will not be difficult to determine such a breakdown by the lack of charge in the smartphone battery.
The device can short-circuit if the internal insulation or the cable connected to the phone melts, or if a thin copper wire gets onto the plug contacts while connecting the charger to the mobile device.
Still have questions or have something to add? Then write to us about it in the comments, this will make the material more complete and accurate.
Many mobile phone users are concerned that their charger gets hot and hot quickly when charging their phone/iPhone or tablet.
Of course, the question arises: should the charger of an Android smartphone, iPhone or tablet heat up?
Typically, it takes power from a wall outlet (usually 220 volts) and converts it to a voltage that can be safely used by a cell phone (about 5 volts).
Only the conversion process is not 100% efficient, and always part of the power remains turns into heat.
This is what causes the charger to heat up. This can be seen primarily when using the fast charging function.
It is better for the phone to avoid the fast charging feature as generating higher voltage also causes the battery to heat up. I recently wrote about how to properly charge your phone to ensure your battery lasts as long as possible.
The fact that cell phone chargers get hot is a natural result of voltage conversion. Therefore, he should not bother us. The fact that the device heats up when charging is absolutely normal applies to all chargers.
The fact that the indicator does not flicker may cause concern - if after a few hours of charging the battery is not charged (stays in the same place as it was), it is worth trying to charge using another one.
When can the charger get hot?
Sometimes excessive heating can indicate a serious electrical problem inside the phone or charger - for example, the diode bridge is heating up - especially if it is from China.
If it gets so hot that you can't touch it, or the plastic casing starts to melt, unplug your phone from the power source as soon as possible.
Does the charger charge your phone quickly?
How do you rate the performance of the charger for your smartphone/iPhone or tablet?
If you suspect it's not charging your smartphone as expected, or you're just curious, there are ways to test it.
This applies to owners of Android phones. The first step is to find out what the reason is by downloading the Ampere application from Google Play.
After installation, launch it and you can start testing right away. To do this, connect the charger to the device and to a power outlet or computer via USB (you can connect it to a powerbank).
In any case, it must be connected to the place where the power is consumed. After about 10 seconds, you will see the measurement results on the left side of the smartphone screen.
You'll also see two different colors of text in the app - orange when the device is plugged in to charge and blue when it's not. In the latter case, you will see how much power is currently being consumed.
The app is very intuitive to use and you'll be able to get the hang of it quickly, I'll just give you a hint that moving the icon to the left will show you all the battery stats (negative numbers mean the battery is getting low).
Remember that if your phone is working very hard at the moment (you have a lot of apps open), you may see worse battery stats, but it won't be a battery fault.
Therefore, it is best to disable all applications in addition to Ampere when testing.
On each USB adapter label, you will find "output" and technical information next to it.
Pay attention to the mA level and subtract from this number the amount you see on your phone display in the Ampere app.
For example, if you have 1000 mA on the charger, then you should expect that charging power minus what is currently loaded by our smartphone (depending on screen brightness), for example 1000 mA - 240 mA = 760 mA.
So as not to bore you, I'll be back in a week with tips on what to do if the USB adapter isn't charging your phone correctly. Good luck.
The charger gets hot and got the best answer
Answer from Yergey[guru]
Lately this is when, with the onset of summer? When did the heat start?
Chargers get hot, sometimes quite hot, this is normal. Pay attention to the time it takes to fully charge, if it hasn’t changed so much that it becomes noticeable and the charge stays about the same as it should, then everything is in order.
It smells like plastic if you sniff it and it smells a little - that’s also okay, especially if it’s relatively new. Do not keep the charger in direct sunlight while working.
If the charging time and battery life have not changed, then everything seems to be in order.
But still, do not leave the charger and other electronics on. devices unattended.
Reply from Qwe[guru]
The starter can get hot, but it shouldn't smell
Reply from GT[guru]
no, this is not normal, at most it should be warm
Reply from Petrovich[guru]
Change your phone battery
Reply from Kirill kirill[newbie]
Chargers come in different capacities, of different quality, and that is why a heating battery or charger is normal. Sometimes the charger itself heated up to such temperatures that it seemed like it would start to burn. Remember the physics lesson, each conductor will heat up from the resistance voltage and current, and if you charge a phone (smartphone) that is not completely discharged, then the residual charge in the battery gives strong resistance and charging charges, but the charging or battery unit will heat up very much. So try it Charge the phone when it turns off, and everything will be okay.