Question: How to charge a laptop if the power controller has failed

I rummaged around in the laptop, poked at the power settings and stumbled on it. That the battery has stopped charging. I thought it was a charging issue. I couldn’t check the charging right away, I checked it three days later, by this time the battery charge had run out, but the charging turned out to be working. I think I disabled something in the settings. . But how can this be done if the laptop is not charging?

P.S. - please don’t troll😅

Answer:
Quote:
It doesn't happen like that.

Question: AMD FirePro W8000 power controller burned out

Good day! There is an AMD FirePro W8000 video card with a burned out power controller. I called several service centers and suddenly encountered a problem that the service centers would not undertake to repair this video card due to a lack of spare parts. Can anyone suggest a suitable service center where they can solve this problem? Location: St. Petersburg. Thanks in advance.

Answer:

Off-topic:

Message from vector554

According to the technician from the service center, they said that the power controller had burned out.

Handsome! There are no words

Question: HP 15-n028sr (DAOU92MB6D0 rev:D) after replacing IT8528E EXA, the laptop turns on but there is no image

good afternoon, we brought this device hp 15-n028sr for repair, with such a problem that when turned on, the charge indicator lights up three times, it turned out that the original charger burned out and after that the person connected a non-original charger, as a result, apparently the power controller which was replaced failed , but after replacing the laptop turns on normally, but there is no image. Tell me where to dig next?

Answer:

ruslanromanenko wrote:

I mean

Well, call a spade a spade...

ruslanromanenko wrote:

but after replacing the laptop turns on normally

That is, absolutely all voltages rise, is there an exchange on the LPC bus?

Question: Toshiba Satellite C660-1V9 (LA-7201P) - Replacing the power controller

Good afternoon everyone, the laptop did not turn on from the mains, only from the battery, the client replaced the charger with another one, the laptop started working. After some time, he decided to clean it from dust and when he took it apart, he noticed rotting legs on the controller which is located on the mother, he cleaned it with a toothbrush and tore off one rotten leg that was holding on to his word of honor, as a result, when turned on, there was no picture on the screen. He decided to unsolder it and replace it with a new one, threw out the old one, and lost the photo.
If it is possible to determine from the board diagram which controller it was, then I ask for help in identifying it.
Laptop: Toshiba satellite c660-1v9
Mother: pwwha la-7201p rev: 1.0

Answer:

Message from andrey541

Although if I had ordered it right away, everything would have arrived long ago

Exactly
In general, I always install new ones... IMHO this is correct

Question: Laptop battery drains when power is connected

Hi all! I have an old laptop, which is generally working. But yesterday we discovered some problems with the power supply: even with the power connected, the battery suddenly begins to discharge. Windows says “plugged in, charging”, but the battery is draining!
I haven’t noticed any patterns yet, it works normally and for no reason at all it can start to discharge. Naturally, the charge reaches 0% and the laptop simply turns off.
The laptop was powerful for its time, even now it is used for design work, it’s a shame to throw it away, it’s also difficult to sell in this condition. I blame the power supply. Does anyone have any ideas what this could be?

Question: When connecting additional food to the mat. board - reboot

I'll start from the very beginning. Turned off the computer and went to bed. In the morning I wake up, and the SCM computer turns on for a second, spins the cooler, and blinks the LED at the mat. board - and reboots. And three seconds later again. I found out experimentally that if you disconnect the additional power from the motherboard, the computer does not reboot, but normally (as far as I can tell, since I disabled the video card, hard drives, etc.) it boots without rebooting. Visually everything is ok with the motherboard. What do you recommend to do, check, see? The only tools are a screwdriver and a soldering iron.

Answer:

Message from kleeez

I found out experimentally that if you disconnect the additional power from the motherboard, the computer will not reboot

This means there is a short circuit in the processor circuits. Check (call) the field switches of the power supply system and the microcontrollers for their control. If one of the transistors is replaced. It is also possible that the condensers are swollen.

Question: The Asus X550VC laptop does not start until you connect the power

Forum members, good day!
Today the Asus X550VC laptop stopped turning on until you connect it to the power supply.
How it happened - in the morning I turned it on from the battery and worked for about 20 minutes. , then, when the charge was about 30%, I connected it to the power supply and continued to use it for about 5 more hours without any special loads, just surfing the Internet and installing and uninstalling, for the sake of testing one program (Ansys 15).

Afterwards everything finished working as usual and after about 5 hours I tried to start it again on battery...
The laptop simply does not start, nor does it respond in any way to the power button, but if you connect it to powered laptop power cord plugs into normal mode and loads the OS and works as always.
If, after starting in operating mode, you pull out the power cord, the laptop simply goes out and turns off.
While operating from the mains, the battery charge shows 81% with the mark “Charging” and after 2-3 hours it has not moved from 81%...

There were no impacts, spills, or replacement of anything; it worked well and was used with care.
The laptop is 2 years and 4 days old.
OS Windows 7 64bit, proc. i5-3230m, video Nvidia GeForce 720m, RAM 4gb, HDD 500gb.

According to observation, the power socket is slightly loose (maybe from time to time), but everything is inserted tightly.
Even if you connect the power cord but not powered into the 220 network The charging indicator lights up (orange), then if you press the power button, it seems to try to start for half a second, but it immediately turns off and goes out along with the orange indicator.
I don’t know what to think, but the battery worked as always, I tried to let it work, discharged it, and charged it to full.
Maybe someone had something similar?
Thanks everyone for your help!

Answer: Performed diagnostics:
powercfg.exe -energy

Battery: Last Full Charge (%)
During the last full charge, the battery was charged to less than 50% of its rated capacity.
Battery code ASUSTeKX550A30
Estimated capacity 44250
Last full charge 18345
Last full charge (%) 41

Does this indicate battery failure?
There were no problems with the battery, it’s surprising that it failed 100% all at once...
In most cases, I observed a long and slow process.
The full report is attached.

Question: Laptop won't charge

Good day. There is a problem with charging the laptop - if I connect the power, then almost immediately either 2 lights start blinking, or the charging light starts to light up and go out (as if there are bad contacts and the connection is lost and appears again) or it doesn’t charge at all (just one light is on , responsible for the operation of the laptop). I tried to remove the battery and work on the mains power alone, it worked for about half an hour - then it turned off. Turned it on again, went into the game - after 10 minutes it turned off. I also noticed that if the lights start flashing and the power goes out, and then unplug the plug from the network, the lights continue to flash until I pull the plug out of the socket. Also, if you completely disconnect the charging from the power supply and let it sit idle for some time, then when connected, it charges normally for a while, but then it still stops. It also happens that it charges normally, then the contact is lost (only one light is on), then it finds contact again. This happened once before; I couldn’t charge my laptop for several days, but then it all went away on its own. The laptop itself is ACER Aspire E5-571G-52Q4. What can you recommend? Thank you.
This time I took it to the same service center. According to the results of their diagnostics:
According to the manager, the breakdown of the cooler is due to the incorrect operation of the power controller on the board, which is why the controller produces power surges and the cooler wears out. They also want to replace the cooler and lubricate everything.

Please tell me how meaningful it is to replace/repair this “controller”, since for this alone they would charge me 4,600 rubles, in addition to 2,200 rubles for work and 800 rubles. for the cooler.
It seems to me that the controller has no effect here and replacing the thermal paste, cleaning and replacing the cooler is enough.

I would be very grateful for your opinion!

Answer: If the fan speed changed depending on the temperature, then the controller and fan worked, but the grinding noise of the fan indicates its wear, it needs to be changed, see the price for yourself, if you don’t agree, look for another service.

Question: The laptop does not switch to battery power

ASUS laptop X550L, 1.5 years old.
Somehow I turned it on without a connected power supply, did my business and turned it off. After a couple of hours I discovered that it doesn’t work without a power supply. He sees the battery, writes that 92% is charged, charges, but nothing happens. Without a power supply, it doesn’t even turn on. All power comes from the power supply, apparently does not use the battery in any way. You can do something at home, while there is no way to carry it to SC.
Previously, there was still a problem when you picked up the laptop and it went into sleep mode on its own.

Answer: Everything somehow fixed itself, everything works, but I think it wouldn’t hurt to take it to the service center. The laptop lives its own life or the fixies have arrived.

Replacement of the Acer tablet charge controller is carried out under conditions that guarantee proper operation of the device. Tablets are being replaced to modern man a lot of things - they record a variety of necessary information - from the daily schedule to PIN codes and passwords. Therefore, the service of urgent tablet repair is popular. The cost of work and the timing of the repair operation are determined on the day of visiting the Service Center. Component replacement steps:

• Acer tablet diagnostics;
• Disassembly;
• Replacement process;
• Guarantees.

Acer tablet diagnostics

The charge controller is a chip that is integrated into the motherboard. It is responsible for the charge and discharge cycles of the device. In fact, the battery life and the amount of energy it can accept depends on it. The spare part requires careful handling.

A problem with the power chip is less common than a failure of the battery or power connector. Therefore, to determine the exact cause of the breakdown, the Acer tablet is diagnosed. This procedure indicates the condition of the hardware and determines the presence of hidden defects.

Malfunctions of the “power microcircuit” can lead to battery failure. The battery is designed for a limited number of full discharge/charge cycles, after which the ability to store energy gradually dries up. Controller at incorrect operation messes up the battery settings and disables the device.

Disassembly

Since the charge controller is integrated into the motherboard, to replace the charge controller on an Acer tablet, you must open access to the module. To do this, the engineer removes back cover tablet, removes the battery and dismantles the mounting bolts and housing. Then the modules adjacent to the housing are removed. In some Acer models, the motherboard is directly accessible, while in others it is necessary to conduct a more in-depth analysis.

Replacement process

Manipulation is carried out by soldering elements. Due to the small size of the component and the proximity of the integrated elements on the motherboard, the engineer must have “surgical precision”. An infrared soldering station helps him with this - it automates the soldering process, eliminating errors. The old, failed controller is soldered off, and then (observing the specific temperature conditions of the surrounding modules) a new one is soldered in, which is suitable for the tablet computer model being repaired.

Guarantees

Replacing an Acer tablet charge controller is a delicate operation that requires specific equipment and engineer experience to be successful. The service center works only with original parts suitable for this tablet model. Therefore, a long warranty period is provided - up to 3 years. After the repair, the Acer tablet is tested to be turned on in the presence of the user.

Repairing Compal motherboards with “won’t charge” or “won’t turn on” faults, especially after being flooded with liquid, often causes difficulties for technicians. Let's consider a typical power and charge circuit used in Acer laptops, using the LA-6552p platform as an example. This motherboard is installed in Acer 5552 and Emashines E442 laptops. Other motherboards containing the ISL 6251 charger chip are built on a similar principle and have minimal differences.

We will consider in parallel the typical circuit for switching on the ISL6251a charger and those parts of the laptop circuit that are associated with starting and charging the battery.

ISL6251 charger operation and battery charge.

+19V power is supplied to pin 24 of the DCIN charger microcircuit from the power connector through the PD16 diode and PR281 resistor. If you replaced the microcircuit, check if the resistor is intact. Inside the microcircuit, at pin 1 VDD, a supply voltage of +5V is formed, which is then supplied via PR86 to pin 15 VDDP and powers the remaining nodes of the microcircuit. We check the presence of +5V on pin 15.

The VREF pin should have a reference voltage of 2.39v generated by the charger

The ACSET input - the charger detects a 19V supply voltage, which the divider on PR280 and PR282 reduces by 14 times. To do this, the voltage at ACSET must exceed 1.26V, which corresponds to 18.0V at the input. Having detected normal power, the charger lowers ACPRN to a low level and sends a signal to the multicontroller.

The multicontroller communicates with the battery controller and, if charging is necessary, sets a high level at the EN pin of the charger, allowing it to charge.

At the CELLS pin, the multicontroller sets a voltage depending on the number of cells in the battery, thereby indicating to the charger what voltage to supply to the battery.

The CSIN CSIP pins are connected to the power supply current sensor - resistor PR61, and the CSON CSOP pins are connected to the charge current source. If the current exceeds, the charger stops charging the battery.

Thus, to charge the battery, it is necessary that the charger be powered (DCIN = 19v, VDD and VDDP = 5v, VREF = 2.39v), so that it detects power (ACSET >1.26v) and the multicontroller gives it the EN signal.

Generation should start on transistors PQ55 PQ57, the currents on PR61 and PR78 should not exceed the maximum permissible values. It should be noted here that in addition to the PR61 PR78 resistors themselves, PR74 PR76 PR72 PR73 may also burn out, which is why the charger may not measure currents correctly.

Operation of LA6552p power circuits. Initial start-up and appearance of voltages.

For the laptop to work, it is necessary that the entrance field effect transistors PQ14 PQ15. They are opened by the PQ68B transistor. It is also opened by a high level of the PACIN signal. Transistors PQ68A, PQ21, PQ19 are blocking - a low level on the gate of PQ68A leads to reliable closing of PQ14, PQ15. This can also happen if the multicontroller raises the ACOFF signal.

Now let's see where PACIN comes from. From the diagram we see that from 6251VDD through resistor PR286. In addition to this, PQ67 must be closed, for which the charger must detect the presence external power supply(ACSET pin) and lower the ACPRN signal.

By the way, ACSET is formed not from the VIN voltage from the connector, but from the PreCHG voltage, which, in turn, is already formed from VIN by four resistors PR124-PR127, therefore, if the latter are broken, the charger will not see the connected adapter.

Starting PWM RT8205, standby voltages +3 and +5

On this platform, standby voltages are generated only when powered by the adapter.

Let's consider the operation of a laptop without a battery, since when repairing motherboard Usually the master does this, powering the board from a laboratory power supply. After connecting the adapter, VIN and PreCHG appear. Through resistor PR128 it goes to the base of PQ34, opening it, and it, in turn, opens PQ31, supplying PreCHG to B+. Since no nodes are running yet, there is no consumption on B+, the capacitors connected to B+ are charged through resistors PR124-PR127

When the B+ voltage reaches enough to start the RT8205, the +3VLP and VL voltages appear. And then, if the startup is not blocked by transistors PQ63A, PQ63B, voltage +3ALWP and +5ALWP For startup to occur, PQ64 must be open. For this to happen, voltage VS must be present and ACPRN must be low. VS is taken from VIN through resistors PR10 PR11.

When on battery power, VS is absent and appears when you press the power button. Thus, when powered by a battery in standby mode, the RT8205 generates only +3VLP and VL.

Many Compal platforms have similar designs. Some may apply operational amplifiers for generating ACSET and other signals. In these nodes, a 3V RTC voltage can be used to generate the reference voltage; such boards do not start if the clock battery is low.

At one time, laptops gained immense popularity due to the ability to run on a battery, which made it possible not to be confined to one place and to do the necessary work almost everywhere. The first models could last only a short time without a charge, and the nickel-metal hydride batteries used had a lot of disadvantages. But manufacturers did not sit idly by, and over several decades, battery manufacturing technologies have undergone dramatic changes. Today, the vast majority of laptops use lithium-ion batteries. They can last quite a long time and lack many of the disadvantages of their predecessors.

However, they are not perfect and may also become unusable over time. A battery malfunction means that it discharges very quickly, or the laptop does not display the charge level correctly. In this case, manufacturers and sellers of equipment recommend purchasing new battery. But since the cost original component quite high, you can try to correct its operation yourself. Depending on the degree of damage, it is necessary to either replace the battery cells, or it will be enough to reset the laptop battery controller.

Note that the battery controller is electronic device and it can also fail. If this happens, the battery will not work at all. Then all the tips below will not help - the controller will need to be repaired by a service center or the battery replaced. However, if the battery works at least somehow, then the controller is functional. It only shows incorrect charging values, quickly charges or discharges the battery, and this can be dealt with.

It is the latter possibility that we want to talk about in more detail in today’s material. You will be able to find out in what cases you need to reset the controller, and we will also tell you about possible ways how you can do it yourself at home.

First, it's worth finding out what a battery controller is. This is a small microcircuit built into the battery itself that controls its operating condition, as well as the charging and discharging process. It interacts with the power controller on the motherboard of the laptop itself, and also transmits the necessary system information to the operating system. We hope the diagram is clear to you. We tried to describe everything in simple words, but if you want to know the technical details, search on the Internet.

When this small chip stops working correctly, you may need to reset the controller. This procedure is also popularly known as battery calibration. By and large, there are only two situations when this may be required: incorrect charge display and replacement of battery cells.

Under incorrect display charge, one should understand the situation when operating system Even after a long charge, the laptop shows that the charge level is less than 100%, or the charge drops sharply, and the laptop does not turn off after a few hours, as it should, but much faster. Many people begin to think that the battery has become unusable, but this is not always the case. The problem very often lies in its controller, which simply does not display the charge correctly.

By replacing battery cells we mean that in some workshops and service centers may offer so-called battery repacking, that is, replacing internal units that have become unusable. After this, the controller must be reset so that all new elements are recognized and can be used correctly. Although, if after replacing the blocks something does not work correctly, you have every right to make a claim and demand that the defects be corrected.

Now let's look at how to reset a laptop's battery controller. Let's touch on the software and manual methods.

Controller soft reset

On some sites you may see a recommendation to use the Battery EEPROM Works program. This is truly a very powerful and advanced utility that can, in some cases, literally revive the battery. But there is one big BUT! To use it, you need to know a lot and be able to understand electrical circuits, as well as have the necessary adapters, which are not always easy to get on the open market. We will not recommend this program for use in home devices, as it is very easy to permanently damage the battery. What then is right for you?

Battery EEPROM Works window

Almost every manufacturer has built-in power management utilities. It can be downloaded from the support site, on the driver download page for your device, and in some cases the utility can be either pre-installed or recorded on the included driver disk. Select the reset or calibration option and follow the on-screen instructions exactly. Most often, the utility discharges the battery to zero, after which it charges up to 100%. The controller will remember the extreme charge level indicators and will work as it did immediately upon purchase.

Different laptops may use different software provided by the manufacturer. Let's look at some popular models:

• Acer - BatteryMark utility tests the battery, fully loading the processor. If inconsistencies are noticed in its operation, a reset and several charge-discharge cycles are performed.
• Asus has a Smart Battery Calibration option in the BIOS on the tab. Here you can reset all controller data.
• Dell - here you need to look at the utility for your model on the official website of the manufacturer. If it is not there, you can use other programs, for example, Smarter Battery.
• HP – on the manufacturer’s website there is an HP Support Assistant utility, which has a “Check Battery” option.

However, if you still want to do full reset controller, you will have to learn how to work with the Battery EEPROM Works program. But keep in mind that you do this at your own peril and risk, so it’s worth experimenting if you don’t mind throwing away the battery if it fails. This utility allows you to:

• Resets the battery charge-discharge cycle counter.
• Changes the release date of the battery to the system notebook.
• Flashes in the controller real capacity batteries.

After this, the battery is considered “new”. Correcting the actual charge can help if the controller shows it incorrectly and the laptop quickly shuts down even though the battery may still be working. This must also be done after replacing the battery cells with new ones. Let us remind you once again - first learn how to use this program, as it allows you to do a lot.

Manual controller reset

If for some reason you cannot find or install the power management utility, you can reset or calibrate the battery manually. How?

1. Disconnect the laptop from electrical network, then put it into BIOS mode. You can read more in the article how to start BIOS mode.
2. Leave the laptop and do not touch it until it is completely discharged. Take care that it does not overheat.
3. Without turning on the laptop, put it on charge. Wait until it is fully charged; to do this, you can leave it overnight.

In 99% of cases, such simple steps will help bring the battery back to life. Well, if this doesn’t help, buy a new battery, or connect the laptop directly to the outlet, removing the battery.

• If you only use your laptop at home, then to reduce wear on its battery, it would be better to remove it. But before that, charge it to about 80% and also check the charge level from time to time as it is prone to self-discharge. After removing, connect the laptop to the power supply and use it as desktop computer. This option is suitable for those who have a laptop in only one place, since with this use you can lose data if you disconnect the laptop from the power source while working.
• To increase the operating time of your device, set the appropriate parameters in the power plan settings. If necessary, use the power saving mode.

Conclusion

Friends, today we talked about how to reset a laptop charge controller. We learned that sometimes the problem lies not only in the computer hardware, but also in software. Therefore, there is no need to rush to order a new battery right away. We hope everything worked out for you and there are no questions left. Don't forget to share your opinion in the comments.

The laptop battery consists of several groups of “cans” - lithium-ion batteries connected in a series-parallel connection. The capacity of batteries decreases over time, which leads to a decrease in time battery life and the need for repairs. In addition, they have to be changed after a deep discharge, when the battery has been lying idle for some time.

The normal lifespan of a switch is 3-4 years, 5-6 years is the maximum lifespan declared by the manufacturer. With frequent use and charging of the laptop, within a year or half you will begin to notice signs of battery wear. Most often they appear like this:

• In offline mode, the laptop's operating time is reduced.
• The battery charge indicator is "lying".
• "Battery Wear level" indicator in various programs exceeds 25%.

The actual state of the battery can be viewed in free utility BatteryInfoView. It uses data from the controller of the battery itself; if the controller is faulty, the data may not be displayed or displayed incorrectly.

The battery diagram usually includes 4, 6, 9 or 12 batteries, so-called cells (cells) or in slang, “cans”. If these “cans” are heavily worn, the battery may swell. This can also happen due to overvoltage. Sometimes a battery can leak: if the jars in which the electrolyte is stored are very leaky, then it can leak through them. Such a battery should be removed and never charged again. Damaged batteries are replaced by resoldering.

New 6 cell battery

Typical symptoms of faulty cans:

• the battery does not hold a charge;
• instant shutdown of the laptop after disconnecting the power supply;
• the laptop recognizes the battery, but the charge level does not change;
• the presence of visual defects, such as swelling, leaking electrolyte, burnout of the housing, or strong heating when connected to the network.

Electronics

The laptop battery charging circuit also includes controller is a microcircuit that ensures uniform charge distribution, as well as protection against overcharging, overheating and other malfunctions. Lithium-ion batteries are considered quite capricious: any deviation in the charging process can lead to fire and explosion. The controller also stores information about the number of charge and discharge cycles.

The controller disconnects the battery from the outside world (opens the circuit) after the charging voltage reaches 4.7 volts. Also, shutdown occurs when the voltage drops to 2.5 volts during discharge. This device helps prevent irreversible changes in the battery.

The battery design provides a protective shutdown when the temperature reaches 80─90 degrees thanks to the built-in thermostat and temperature sensor. IN lithium-ion batteries more than in other types of batteries, all kinds of fuses. This is necessary because lithium is a very reactive metal. The controller monitors the state of charge of the battery as a whole and all elements separately.

also in Li-Ion batteries There are many different sensors and protections to ensure this. Here are some:

• General current fuse (recoverable);
• A fuse on each battery cell that operates at a temperature of 80–90 degrees C;
• Protection against excess pressure in the battery cell. The critical value is 10 kgf/cm2. Protection is not restored;
• Circuit for monitoring charging and general condition of the battery.

The activation of any sensor either turns off a separate bank, or stops charging the entire battery completely.

Interaction of the battery controller with motherboard occurs via the bus SMBus. To connect the battery to the board, use a connector with at least 5 pins. Of these, two are responsible for supplying power, two more provide data exchange about the state of the battery and the state of charge, completed charge-discharge cycles, information about the manufacturer, etc. Some parameters are given below:

• Current state;
• type of battery cells;
• identifier;
• serial number;
• dates of production and first use;
• manufacturer
• number of charge-discharge cycles performed.

Most laptops available in the market have batteries with connectors 6, 7, 9 contacts. You have to look for the pinout for a specific laptop on the manufacturers’ websites or manuals. The pinout of the most common seven-pin laptop battery connector is as follows:

1. NC (No Contact);
2. SCL/SDA (used for communication between microcircuits);
3. BATT_IN (connection signal);
4. SMB (battery status bus);
5. DATA-(null);
6. DATA+ (main voltage).

IN battery a separate electrical line is allocated for transmitting an identifier (ID), which is a sequence of codes. The pinout of such batteries includes the following contacts:

• thermistor;
• general conclusion.

The identification pin in the battery is provided by a clock generator. This element produces a signal in the form of electrical impulses. For the interface to function, two lines are required. With their help, information is transferred between the battery and the motherboard.

As you understand, if the generator or thermistor malfunctions, the battery will not be detected by the laptop.

Typical symptoms of a malfunctioning controller, generator or wiring circuit:

• The laptop does not see the battery. Despite the fact that the battery is intact and connected to the laptop, it does not recognize it and displays a notification that the battery is missing;
• The laptop detects the battery, but the charge does not start;
• When the battery is connected, the laptop does not start, but after removing it and connecting it directly from the mains, it turns on immediately. This symptom will indicate that there is a short circuit inside the battery.

Firmware

The battery exchanges more than just identification information with the laptop electronics. She stores a lot of other information about herself and her current state. To store all this data in the battery, a non-volatile programmable EEPROM memory is provided in the form of a chip with a serial interface. It contains factory information about the full capacity, serial number, manufacturer, etc. Its contents can be reflashed if necessary.

Most often, flashing is performed through a program Battery EEPROM Works. Flashing must be performed when you have installed new banks in order to reset the charge cycle counter and the full capacity of new cells (Full Charge Capacity):

Battery EEPROM firmware

Incompatibility of batteries and power supplies

The main reason for battery controller failures is that instead of the original laptop battery, they use Chinese analogues purchased from online stores such as Aliexpress and Ebay. In this case, the problem may manifest itself immediately, after connecting the device to the power supply, or after several charging cycles. The main reason for the incompatibility is that the motherboard fails to recognize the battery controller.

In order to check a power supply of questionable quality, you need to connect a known good battery to the laptop. If the laptop works stably with it and the battery charges, then the problem is in the newly purchased power supply.

Some laptop manufacturers use a special original power supply recognition system. Sony, HP, Dell (some models), Lenovo laptops have this function. For example, if you connect someone else’s or non-original power supply to one of these laptops, then the battery may not charge. Yes, the laptop will turn on and work, but only from the network.

Diagnostics of the charge circuit on the motherboard

As was initially said, the battery may not charge due to no fault of its own, namely the fault of the charging circuit on the motherboard.

The battery charging process is controlled from the board by a PWM controller chip - charger. Switching power circuits from a power source (battery or power supply) to the laptop board by supplying control signals to transistor switches (MOSFETs) is the main task of the charger. The charger is also responsible for reporting the connection of the power source to other system controllers and generating voltages and currents to charge the battery.

There are a huge number of different modifications of PWM charge controllers used in laptops. This is due to the fact that power consumption and voltage are different in different platforms. The most popular are chips from RT (RICHTEK), MAX ( Maxim Integrated), ISL (Renesas, Intersil), SEMTECH (SX), Texas Instruments (TPS, BQ).

Let's look at the charger circuit using the BQ24707 as an example.

Simplified connection diagram BQ24707

When you connect a power supply connected to the power supply (usually 15-19 V) to a laptop, voltage appears on one of the charger contacts (in the example above it is transmitted through the Adapter Detection line circled in red) - this is how the power supply connection is recognized. Having learned that the adapter is connected, the charger informs one of the main control chips about this - the EC/KBC controller (also known as a multicontroller) or the south bridge, which are indicated in the figure by the “Host” rectangle. In some implementations, both chips receive information.

If the input voltage level from the power supply meets the required level (for most laptops this is 19 V), the EC/KBC controller closes the switch (BATFET, circled in blue), which passes power from the battery to the board. At the same time, switches Q1 and Q2 are opened, operating in antiphase with BATFET. Q1 passes power from the 19 V line to the charger itself, and through Q2 the voltage from the power supply is supplied to the rest of the system consumers. It also charges the battery.

Here is a typical connection diagram:

Using a separate channel, the charger monitors the battery voltage level. When the maximum is reached, charging stops.

• ACDET - adapter presence detection input
• SCL - SMBus bus clocking
• SDA - SMBus data
• SRN and SRP are negative and positive inputs of current sensors. SRN is also used to determine battery voltage.
• PHASE and LODRV are the upper and lower legs of the MOSFET power output.
• ACN and ACP - current test inputs

If you pay attention to the lines that go to and from the Charger, you will notice that they are studded with small parts called trim pieces. Each of these elements can fail at any time. This is what will cause the lack of charging and a number of other problems with the battery.
Incorrect operation of the charging system is accompanied by the following symptoms:

• The laptop does not recognize the working battery
• Laptop sees new battery, but does not charge it.
• When you plug your computer into a power outlet, the battery indicator is active, but the battery is not actually charging.
• The battery is fully charged, but the laptop is not receiving power. If you disconnect it from the power supply, the computer turns off immediately.

By solving problems with the charge controller, you will simultaneously solve problems with turning on the laptop.

Many controllers are similar to each other and are interchangeable. You can study this dedicated to this issue.