If you need MacBook charging repair in Moscow, contact Yudu specialists. The technicians registered on our website will conduct computer diagnostics, determine the causes of the breakdown and quickly restore full operation of the charger. It can be repaired on the same day you call.
Yudu performers will fix any problem in a laptop with an apple logo. They will repair the power supply, charge controller, adapter and connector. Also, if necessary, they will replace the cable on the charger so that the MacBook Air begins to fully charge.
Service center services are required if:
When MacBook Pro charging cannot be repaired, Yudu's performers will recommend purchasing a new charger. If the problem is in the MacBook itself, a specialist will carefully check all the parts that are responsible for charging the battery and repair the necessary elements.
The weak point of the MacBook Air is the cable. Over time, it frays at the joints. The integrity of the cable can be damaged mechanically. Supplying power through a damaged cable may cause problems with other parts of your Mac.
More modern MacBook Air models do not have such problems, since they have a built-in adapter. But after contact with moisture, it may stop working and you will need professional help.
When the first signs of inoperability of the original charger appear, seek help from specialists. They will match the adapter to your laptop model, as the MacBook Air and MacBook Pro 2013 have different adapters.
Repairing a MacBook Pro charger in Moscow does not require large financial costs. This is a simple action that Yudu performers perform often. They will quickly and inexpensively eliminate all damage and consequences of exposure to moisture. As a result, you will receive a fully functioning MacBook that will turn on in a timely manner.
Our site's technicians will repair the device and eliminate all faults that are discovered during diagnostics. The craftsmen registered with Yuda have been repairing Apple equipment for many years, so you can rest assured of their professionalism.
Cooperation with Yudu performers is beneficial because they:
Once the problem is fixed, the laptop will work perfectly, and rapid discharge will no longer complicate the operation process.
Order the services of Yudu specialists who will ideally repair your MacBook charging and will be able to return the laptop with the Apple logo to its previous functionality.
Have you ever wondered what's inside your MacBook charger? The compact power supply contains significantly more parts than you might expect, including even a microprocessor. In this article, we will be able to disassemble the MacBook charger to see the numerous components hidden inside and find out how they interact with each other to safely deliver much-needed electricity to the computer.
Most consumer electronics, from your smartphone to your TV, use switching power supplies to convert alternating current from a wall outlet to the low-voltage direct current used by electronic circuits. Switching power supplies, or more correctly secondary power supplies, get their name from the fact that they turn on and off the power supply thousands of times per second. This is the most efficient for voltage conversion.
The main alternative to a switching power supply is a linear power supply, which is much simpler and converts surge voltage into heat. Because of this energy loss, the efficiency of a linear power supply is about 60%, compared to about 85% for a switching power supply. Linear power supplies use a bulky transformer that can weigh up to a kilogram or more, while switching power supplies can use tiny high-frequency transformers.
Nowadays such power supplies are very cheap, but this was not always the case. In 1950, switching power supplies were complex and expensive, used in aerospace and satellite applications that required a lightweight, compact power supply. By the early 1970s, new high-voltage transistors and other technological improvements made batteries much cheaper and were widely used in computers. The introduction of single-chip controllers in 1976 made power converters even simpler, smaller and cheaper.
Apple's use of switching power supplies dates back to 1977, when chief engineer Rod Holt designed a switching power supply for the Apple II.
According to Steve Jobs:
This switching power supply was as revolutionary as the Apple II's logic. Rod didn't get much recognition in the pages of history, but he deserved it. Every computer now uses switching power supplies and they are all similar in design to Holt's design.
This is a great quote, but it's not entirely true. The power supply revolution happened much earlier. Robert Boschert began selling switching power supplies in 1974 for everything from printers and computers to the F-14 fighter jet. Apple's design was similar to earlier devices and other computers did not use Rod Holt's design. However, Apple has made extensive use of switching power supplies and is pushing the boundaries of charger design with compact, stylish and cutting-edge chargers.
For analysis, we took a Macbook 85W charger model A1172, the dimensions of which are small enough to fit in the palm of your hand. The figure below shows several features that can help distinguish an original charger from counterfeits. A bitten apple on the body is an integral attribute (which everyone knows), but there is a detail that does not always attract attention. Original chargers must have a serial number located under the ground pin.
As strange as it may sound, the best way to open the charge is to use a chisel or something similar and add a little brute force to it. Apple initially objected to anyone opening their products and examining the “internals.” Removing the plastic case, you can immediately see the metal heat sinks. They help cool the power semiconductors housed inside the charger.
On the back of the charger you can see the printed circuit board. Some tiny components are visible, but most of the circuitry is hidden under a metal heatsink held together with yellow electrical tape.
We looked at the radiators and that was enough. To see all the details of the device, you naturally need to remove the heat sinks. Hidden beneath these metal parts are significantly more components than you would expect from a small unit.
The image below shows the main components of the charger. The AC power enters the charger and is then converted to DC. The PFC (Power Factor Correction) circuit improves efficiency by providing a stable load on the AC line. In accordance with the functions performed, the microcircuit can be divided into two parts: primary and secondary. The primary part of the board, together with the components placed on it, is designed to lower the high-voltage direct voltage and transmit it to the transformer. The secondary part receives a constant low-voltage voltage from the transformer and outputs the constant voltage of the required level to the laptop. Below we will look at these schemes in more detail.
AC voltage is supplied to the charger through the removable plug of the mains cable. The big advantage of switching power supplies is their ability to operate over a wide range of input voltages. By simply changing the plug, the charger can be used in any region of the world, from European 240 volts at 50 gigahertz to North American 120 volts at 60 gigahertz. Capacitors, filters, and inductors in the input stage prevent interference from leaving the charger via the power lines. The bridge rectifier contains four diodes that convert AC power to DC power.
Watch this video for a clearer demonstration of how a bridge rectifier works.
The next step in the charger operation is the power factor correction circuit, marked in purple. One problem with simple chargers is that they only receive a charge for a small portion of the AC cycle. When a single device does this, there are no particular problems, but when there are thousands of them, it creates problems for energy companies. This is why regulations require chargers to use power factor correction techniques (they use energy more evenly). You might expect that poor power factor is caused by switching power transmission that switches on and off quickly, but this is not a problem. The problem arises from a non-linear diode bridge that charges the input capacitor only when the AC signal peaks. The idea of PFC is to use a DC-DC boost converter before switching the power supply. Thus, the sine wave output current is proportional to the AC waveform.
The PFC circuit uses a power transistor to precisely chop up the AC input tens of thousands of times per second. Contrary to expectations, this makes the load on the AC lines smoother. The two largest components in the charger are the inductor and PFC capacitor, which help boost the DC voltage to 380 volts. The charger uses the MC33368 chip to trigger the PFC.
The primary circuit is the heart of the charger. It takes high DC voltage from the PFC circuit, chops it up and feeds it into a transformer to generate a low voltage output from the charger (16.5-18.5 volts). The charger uses an advanced resonant controller that allows the system to operate at a very high frequency of up to 500 kilohertz. The higher frequency allows for more compact components to be used inside the charger. The IC shown below controls the power supply.
SMPS controller - high voltage resonating controller L6599; For some reason it is labeled DAP015D. It uses a half-bridge resonant topology; In a half-bridge circuit, two transistors control power through a converter. Common switching power supplies use a PWM (pulse width modulation) controller that adjusts the timing of the input. L6599 corrects the frequency of the pulse, not its pulse. Both transistors are turned on alternately for 50% of the time. When the frequency increases above the resonant frequency, the power drops, so frequency control regulates the output voltage.
The two transistors are alternately turned on and off to lower the incoming voltage. The converter and capacitor resonate at the same frequency, smoothing out the interrupted input into the sine wave.
The second half of the circuit generates the charger output. It receives power from the converter and, using diodes, converts it into direct current. Filter capacitors smooth out the voltage that comes from the charger through the cable.
The most important role of the secondary part of the charger is to maintain dangerously high voltages within the charger to avoid potentially dangerous shock to the end device. The insulation boundary, marked with a red dotted line in the image above, indicates the separation between the main high-voltage part and the low-voltage secondary part of the device. Both sides are separated from each other by a distance of about 6 mm.
A transformer transfers power between the primary and secondary devices using magnetic fields instead of a direct electrical connection. The wires in the transformer are triple insulated for safety. Cheap chargers tend to be stingy with insulation. This creates a security risk. Optocoupler uses an internal beam of light to transmit a feedback signal between the secondary and primary parts of the charger. A control chip in the primary part of the device uses a feedback signal to adjust the switching frequency to keep the output voltage stable.
The unexpected component of the charger is a miniature printed circuit board with a microcontroller, which can be seen in our diagram above. This 16-bit processor constantly monitors the charger voltage and current. It enables transmission when the charger is connected to the MacBook and disables transmission when the charger is disconnected. The charger shuts down if there is any problem. This Texas Instruments MSP430 microcontroller is about the same power as the processor inside the first original Macintosh. The processor in the charger is a low power microcontroller with 1 KB of flash memory and only 128 bytes of RAM. It includes a high-precision 16-bit analog-to-digital converter.
The 68,000 microprocessors from the original Apple Macintosh and the 430 microcontrollers in the Charger are not comparable because they have different designs and instruction sets. But for a rough comparison, the 68000 is a 16/32 bit processor running at 7.8MHz, while the MSP430 is a 16 bit processor running at 16MHz. The MSP430 is designed for low power consumption and uses approximately 1% of the power supply of the 68000.
The square orange pads on the right are used to program the chip during production. The 60W MacBook charger uses the MSP430 processor, but the 85W charger uses a general purpose processor that needs to be flashed. It is programmed with a Spy-Bi-Wire interface, which is TI's two-wire variant of the standard JTAG interface. Once programmed, the security fuse in the chip is destroyed to prevent the firmware from being read or modified.
The three-pin IC on the left (IC202) reduces the 16.5 volt charger to the 3.3 volt required by the processor. The voltage on the processor is not provided by a standard voltage regulator, but by the LT1460, which produces 3.3 volts with an extremely high accuracy of 0.075%.
Flipping the charger over onto the circuit board reveals dozens of tiny components. The PFC and power supply (SMPS) controller chip are the main integrated circuits that control the charger. The voltage reference chip is responsible for maintaining a stable voltage even when temperature changes. The voltage reference IC is the TSM103/A, which combines two op-amps and a 2.5V reference in a single-chip circuit. Semiconductor properties vary significantly depending on temperature, so maintaining a stable voltage is not an easy task.
These chips are surrounded by tiny resistors, capacitors, diodes and other small components. The MOSFET output transistor turns the output power on and off as directed by the microcontroller. To the left of it are resistors that measure the current being sent to the laptop.
The insulation boundary (marked in red) separates the high voltage from the low voltage output circuit for safety. The dotted red line shows the insulation boundary that separates the low voltage side from the high voltage side. Optocouplers send signals from the secondary side to the main device, turning off the charger if there is a problem.
A little about grounding. A 1KΩ ground resistor connects the AC ground pin to the base at the charger output. Four 9.1MΩ resistors connect the internal DC base to the output base. Since they cross the isolation boundary, security is an issue. Their high stability avoids the risk of shock. The four resistors are not actually required, but the redundancy exists to ensure the safety and fault tolerance of the device. There is also a Y capacitor (680pF, 250V) between the internal ground and the output ground. T5A fuse (5A) protects the ground output.
One reason to install more control components in a charger than usual is the variable output voltage. To deliver 60 watts of voltage, the charger provides 16.5 volts with a resistance level of 3.6 amps. To produce 85 watts, the potential increases to 18.5 volts and the resistance is correspondingly 4.6 amperes. This allows the charger to be compatible with laptops that require different voltages. As the current potential increases above 3.6 amperes, the circuit gradually increases the output voltage. The charger turns off immediately when the voltage reaches 90 W.
The control scheme is quite complex. The output voltage is controlled by an op-amp in the TSM103/A IC, which compares it with a reference voltage generated by the same IC. This amplifier sends the feedback signal through an optocoupler to the SMPS control IC on the primary side. If the voltage is too high, the feedback signal lowers the voltage and vice versa. This is a fairly simple part, but where the voltage increases from 16.5 volts to 18.5 volts things get more complicated.
The output current creates a voltage across resistors with a tiny resistance of 0.005Ω each - they are more like wires than resistors. The operational amplifier in the TSM103/A chip amplifies this voltage. This signal goes to the tiny TS321 op amp, which triggers the ramp when the signal reaches 4.1A. This signal enters the previously described control circuit, increasing the output voltage. The current signal also goes into the tiny TS391 comparator, which sends the signal to the primary device through another optocoupler to reduce the output voltage. This is a protection circuit if the current level becomes too high. There are several places on the PCB where zero resistance resistors (i.e. jumpers) can be installed to change the gain of the op amp. This allows the gain accuracy to be adjusted during manufacturing.
The Magsafe magnetic plug that connects to a Macbook is more complex than it might seem at first glance. It has five spring-loaded pins (known as Pogo pins) for connecting to the computer, as well as two power pins, two ground pins. The middle pin is the data connection to the computer.
Inside, Magsafe is a miniature chip that tells the laptop the serial number, type and power of the charger. The laptop uses this data to determine if the charger is original. The chip also controls an LED indicator for visual status indication. The laptop does not receive data directly from the charger, but only through the chip inside Magsafe.
You may have noticed that when you connect the charger to the laptop, one or two seconds pass before the LED sensor is activated. During this time, a complex interaction occurs between the Magsafe plug, the charger and the Macbook itself.
When the charger is disconnected from the laptop, the output transistor blocks voltage from being output. If you measure the voltage from your MacBook charger, you will find approximately 6 volts instead of the 16.5 volts you were hoping to see. The reason is the pin is disconnected and you are measuring voltage through a bypass resistor just below the output transistor. When the Magsafe plug is connected to the Macbook, it starts to draw low voltage. The microcontroller in the charger detects this and turns on the power within a few seconds. During this time, the laptop manages to receive all the necessary information about the charger from the chip inside Magsafe. If everything is fine, the laptop begins to consume power from the charger and sends a signal to the LED indicator. When the Magsafe plug is disconnected from the laptop, the microcontroller detects the loss of current and cuts off the power supply, which also turns off the LEDs.
A completely logical question arises - why is the Apple charger so complicated? Other laptop chargers simply provide 16 volts and immediately supply voltage when connected to the computer. The main reason is for safety purposes, to ensure that no voltage is applied until the pins are firmly attached to the laptop. This minimizes the risk of sparks or arcing when connecting a Magsafe plug.
The original Macbook 85W charger costs $79. But for $14 you can buy a charger on eBay that looks exactly like the original. So what do you get for the extra $65? Let's compare the copy of the charger with the original. From the outside, the charger looks exactly like the original 85W from Apple. Except that the Apple logo itself is missing. But if you look inside, the differences become obvious. The photos below show a genuine Apple charger on the left and a copy on the right.
A copy of the charger has half as many parts as the original and the space on the printed circuit board is simply empty. While the genuine Apple charger is chock full of components, the replica isn't designed for much filtering and regulation and lacks PFC circuitry. The transformer in the copy of the charger (large yellow rectangle) is much larger in size than the original model. The higher frequency of Apple's Advanced Resonating Converter allows the use of a smaller transformer.
By turning the charger over and looking at the circuit board, you can see a more complex circuit of the original charger. The copy has only one control IC (in the upper left corner). Since the PFC circuit is completely thrown away. In addition, the charging clone is less difficult to control and does not have grounding. You understand what this threatens.
It's worth noting that the copy charger uses a Fairchild FAN7602 green PWM controller chip, which is more advanced than you might expect. I think most people expected to see something like a simple transistor oscillator. And in addition, the copies, unlike the original, use a single-sided printed circuit board.
In fact, the copy of the charger is of better quality than you might expect, compared to the terrible copies of iPad and iPhone chargers. The MacBook charger copy does not reduce all possible components and uses a moderately complex circuit. This charger also places a slight emphasis on safety. Isolation of components and separation of high and low voltage areas is applied, with the exception of one dangerous error, which you will see below. The capacitor Y (blue) was mounted crookedly and dangerously close to the optocoupler contact on the high voltage side, creating a risk of electric shock.
The irony is that despite its complexity and attention to detail, the Apple MacBook charger is not a foolproof device. On the Internet you can find a lot of different photos of burnt, damaged and simply non-functional chargers. The most vulnerable part of the original charger is the wire in the area of the Magsafe plug. The cable is quite flimsy and it quickly frays, which leads to its damage, burnout or simply breaking. Apple provides how to avoid cable damage instead of simply providing a stronger cable. The charger received only 1.5 out of 5 stars in a review on Apple's website.
MacBook chargers may also stop working due to internal problems. The photos above and below show burn marks inside the failed Apple charger. Unfortunately, it is impossible to say exactly what exactly caused the fire. Due to a short circuit, half of the components and a good part of the printed circuit board burned out. Below in the photo is burnt silicone insulation for attaching the board.
As you can see, Apple's charger has a more advanced design than its counterparts and has additional security features. However, the genuine charger costs $65 more and I doubt the additional components cost more than $10 - $15. Most of the cost of the charger goes into the company's bottom line. It is estimated that the cost of the iPhone is 45% of the company's net profit. Chargers probably bring in even more money. The price of the original from Apple should be significantly lower. The device has many tiny components—resistors, capacitors, and transistors—that range in price around one cent. Large semiconductors, capacitors and inductors naturally cost significantly more, but for example, the 16-bit MSP430 processor costs only $0.45. Apple explains the high cost not only by the costs of marketing and so on, but also by the high costs of the very development of a particular charger model. The book Practical Switching Power Supply Design estimates 9 months of labor time to design and improve power supplies at around $200,000. The company sells about 20 million MacBooks per year. If you invest the cost of development into the cost of the device, it will be only 1 cent. Even if the design and development costs for Apple chargers are 10 times higher, the price will not exceed 10 cents. Despite all this, I do not recommend that you save your money by purchasing analogue chargers and risking your laptop and even your health.
Users are not often interested in what is inside the charger. But there are a lot of interesting things there. The seemingly simple charging uses advanced technologies including power factor correction and a resonant power supply to produce 85 watts of power in a compact module. The Macbook charger is an impressive piece of engineering. At the same time, its copies strive to make everything as cheap as possible. This is of course economical, but also dangerous for you and your laptop.
They have one unpleasant property - they wear out quite quickly. Sometimes it’s just ugly: the internal “filling” of the wire turns black against the background of the white shell. Sometimes it’s very, very bad, because “charging” stops working. Need to do something! Do you want to save 5 thousand rubles on buying a new accessory? Read our instructions!
In contact with
First of all, disconnect the cable from the network. Further actions depend on its performance.
If the wire has just started to fray and is still charging MacBook, it will not be difficult to correct the situation. All you need to do is buy liquid electrical tape (the price is 300 rubles), apply it to the damaged area using a brush (usually included) and let it dry for an hour. This way you will solve several problems at once: you will prevent further destruction of the wire, avoid problems with the “electrical” part and (if the liquid electrical tape is white) make the repaired wire more elegant in appearance. The same can and should be done with worn-out cables for iPhone and iPad.
If you realize it too late and MacBook no longer charges from a frayed wire - no big deal! For such cases, there is a special step-by-step guide from iFixit. You don't have to be an electrician to do everything right.
If something doesn’t work out, or you don’t want to bother, you can always:
1.
Buy a used cable on eBay or at a local flea market. It is quite possible to save up to 50% of the price of the official accessory.
2.
Take advantage of the one-year standard (if not already expired) or three-year extended (if purchased) Apple warranty.
Good luck in solving the problem - and next time keep an eye on the condition of your “cable” equipment! :)
Fair, not overpriced and not underestimated. There should be prices on the Service website. Necessarily! without asterisks, clear and detailed, where technically possible - as accurate and concise as possible.
If spare parts are available, up to 85% of complex repairs can be completed in 1-2 days. Modular repairs require much less time. The website shows the approximate duration of any repair.
Warranty and responsibility
A guarantee must be given for any repairs. Everything is described on the website and in the documents. The guarantee is self-confidence and respect for you. A 3-6 month warranty is good and sufficient. It is needed to check quality and hidden defects that cannot be detected immediately. You see honest and realistic terms (not 3 years), you can be sure that they will help you.
Half the success in Apple repair is the quality and reliability of spare parts, so a good service works directly with suppliers, there are always several reliable channels and your own warehouse with proven spare parts for current models, so you don’t have to waste extra time.
Free diagnostics
This is very important and has already become a rule of good manners for the service center. Diagnostics is the most difficult and important part of the repair, but you don't have to pay a penny for it, even if you don't repair the device based on its results.
Service repairs and delivery
A good service values your time, so it offers free delivery. And for the same reason, repairs are carried out only in the workshop of a service center: they can be done correctly and according to technology only in a prepared place.
Convenient schedule
If the Service works for you, and not for itself, then it is always open! absolutely. The schedule should be convenient to fit in before and after work. Good service works on weekends and holidays. We are waiting for you and working on your devices every day: 9:00 - 21:00
The reputation of professionals consists of several points
Company age and experience
Reliable and experienced service has been known for a long time.
If a company has been on the market for many years and has managed to establish itself as an expert, people turn to it, write about it, and recommend it. We know what we are talking about, since 98% of incoming devices in the service center are restored.
Other service centers trust us and refer complex cases to us.
How many masters in areas
If there are always several engineers waiting for you for each type of equipment, you can be sure:
1. there will be no queue (or it will be minimal) - your device will be taken care of right away.
2. you give your Macbook for repair to an expert in the field of Mac repairs. He knows all the secrets of these devices
Technical literacy
If you ask a question, a specialist should answer it as accurately as possible.
So that you can imagine what exactly you need.
They will try to solve the problem. In most cases, from the description you can understand what happened and how to fix the problem.
