The Apple iPad sells its charger for $19. However, you can easily purchase the similarly looking charger from online stores for around $3. From the outside, both chargers are very similar. This article will look at the original and imitation chargers to show that the original has much better quality and most importantly safer to use.
External differences between the original and fake charger
When viewed from the outside, the original device on the left and the imitation on the right are very similar. Looking closer at the label, the differences between the two are more apparent. The fake device does not have the words “Designed by Apple in California, Assembled in China” and the manufacturer name “Foxlink” which means “Apple California design, manufactured in China.” The reason for this is probably to escape from legal obligations. However, interestingly, TM and © 2010 Apple Inc. are still in print. The fake device also has many certificate signs like UL, but none of them are real. As you can see in the pictures below, it is not possible to pass security tests.
How the Apple charger and fake charger looks on the inside?
When both chargers are opened, the big difference between them is more noticeable. The original device is full of stuff and barely fit the case. The fake charger on the right contains fewer pieces than the original, and there is more space in it. More expensive and quality components especially capacitors and transformers are used in the Apple charge. As you will see below, these parts make a difference in the quality of the tension coming from the power supply and regarding safety.Something about security is very clear: the isolation of the Apple charge is much better. The high-voltage on top is covered with a yellow insulated tape. Some parts are wrapped with tapered rubber, some insulators between the plastic parts, and some cables have extra insulation. On the other hand, insulation in the imitation device is minimal.
The workmanship and quality of the Apple charger are much higher. Some parts of the fake device are skewed and sloppy. Although this does not affect the performance of the electrical circuit, it indicates that the workmanship is bad.
Looking at the bottom of the circuit boards, it turns out that the Apple charge is much more complicated. There is virtually no space on the Apple circuit board, with tiny pieces of surface mounted (SMT-YMT) on each side. There are only a few components on the dummy device, and more space is available. The red insulating tape on the original device is a protection from an electrical surge.
How Do Apple Charger and Fake Charger Work?
Both the original and fake chargers have similar flyback switching-mode power supply (SMPS) circuit. Switched-mode power supplies are the circuit technology that allows these chargers to be made so small. The fundamental principle of a switched power supply is to open and close the circuit thousands of times at a time. Another advantage of this circuit is the power lost in the heat is kept at the minimum. The high frequency used also allows the transformer to be downsized and to be much smaller than 50/60 Hz heavy transformers.
The Fake Charger
For the imitation charger, the AC voltage is switched on with the white wires on the upper left. Then the current will pass through a fusible resistor, which also serves as a fuse. The bridge rectifier underneath it is turned from AC to DC. The voltage there is between 170-340V (110 or 220V supply voltage). The input capacitor is purifying the rectified voltage through fluctuation. The 4-legged control integration (IC) monitors the output of the charger and switches the switching transistor on and off 41,000 times a second. This DC voltage is applied to the primary coil of the flyback transformer. The transformer will reduce the voltage to the desired 5V. The output capacitor will then smoothen the voltage. Finally, the output voltage is pushed into the USB connector to charge the iPad. Apart from these, there are also several attachments. A feedback winding in the transformer is feeding back control voltage to the control IC. This winding also provides the supply of the IC, and the small capacitor on it (DC power capacitor) corrects DC for integration. Finally, a snubber capacitor turns off voltage spikes that occur at the transistor tip.
The Apple Charger
The original iPad charge shown above works with similar principles. However, the electronic circuit is more complex. The power goes to the AC input in the bottom right. It then passes through a 2-ampere insulator (black insulated for safety). There are far more filters in the primer than the imitation charger; Filter bobbin (common mode shock bobbin), coil and two large electrolytic capacitors. Although they increase the cost, they enhance the quality of the output voltage. On the output side (left) there are two filter capacitors. One of these is a high-quality aluminum polymer capacitor (which looks like pink/purple). Y capacitors help reduce noise. The tiny NTC temperature sensor also turns off the device if the charger overheats.
On the other side of the circuits, the Apple charger is much more complicated than the other. Starting from the AC input on the top right, the charger has extra input filters and spark gap intervals. The restart circuit, allows the charger to reset if there is a fault. The control integration allows full control of the charger under variable conditions. The internal structure of this integration is much more complex than the control integration of the imitation device. The current sense resistor allows the integrated circuit to high-temperature the current through the transformer. Line voltage resistors also detect the input voltage of the integrator (they also provide the power needed to integrate at the first power-up). The protection circuitry uses the temperature sensor on the other side of the board to turn off the device in the event of overvoltage or high-temperature conditions.
The secondary side also includes some features that will improve the output voltage. The Y-cap filter (Y-cap filter) reduces noise in the circuit using Y capacitors. The output filter at the output (output filter) is much more complicated than the Fake one. Also, note that the original charger is grounded. There is only a plastic protrusion in the imitation device instead of this.
Both chargers use Apple’s proprietary system, USB data resistors, and certain voltages on USB data lines to clarify the type of the iPad. On chargers that do not do this correctly, iPad gives the error “Charging is not supported with this accessory.” Thanks to these resistances, the original device says it is an Apple device of 2A, while the fake one sends the information that it is an Apple 1A charger. The imitation is packaged in a 10W package, but it has a 5W charger.
Safety Features Of Apple Charger And Fake Charger
When you plug a phone into your charger, you take for granted the safety features of the charger. However, it is the most important feature for these devices. The voltage in the charger can reach up to 340 volts. If things go wrong, the charger can burn, hurt and even kill you. That is why these chargers and similar devices have gone through very stringent safety standards if you have a reliable manufacturer. These security measures are neglected in counterfeit goods that you buy cheaply. Although the security risks are not noticeable from the outside, you start to see the hazards when you open the inside of the device.
UL guidelines require high voltage and low voltage to be separated from one another at a safe distance. A certain distance is needed for the creepage, and a certain distance is needed through the air. The rules are quite extensive and complex, but in summary, they must be at least 4 mm between the high and low voltage area.
The iPad charger has a safe distance and jumping clearance. The high voltage section is at the top; the low voltage section is at the bottom.
The photo above shows how the original iPad charger distinguishes between the high voltage (bottom) and low voltage (top). The smiley face symbol on the right points to the safe gap between the primary and the secondary (this is deliberately left blank, even though the backrest is full of electronics). This 5.6 mm clearance provides an excellent security area. The smiley face symbol on the left also points to a low and high voltage area separating the high voltage fields.
The image above shows how an insulated sleeve is placed on the cover and how the USB connector is protected. Also, several layers of protection are provided with a red-brown band around it and a yellow band covering the entire high-voltage section.
The surface leakage distance seen on the fake charger on top is frightening with only 0.6 mm between high and low voltage. Just below the sad face symbol, the low-voltage area is close to the high-voltage part almost touching each other. (The lines on the right indicate millimeters.) The left side has proper clearance, the smiley face there points to an apparent gap under the transformer, and there is no safety problem. But in general terms, this device is not secure. If you charge this charger in a damp place and the water concentrates in this 0.6 mm section, the result can be disastrous!
Safety Features of Transformers
For safety reasons, the parts of the charger that contain high voltage and low voltage must be electrically isolated. However, the electric current also has to pass in some way. The flyback transformer uses magnetic fields to transmit power without direct connection. Since the transformer is the largest and most expensive part of a charger, counterfeit manufacturers compromise safety and quality for extra profit. On the photo above, the original transformer (left) is quite large compared to the imitation one (right). The size difference could be a clue that the original charger is of better quality and power efficiency.
The primary safety requirement of a transformer is to separate the high voltage primary circuit and the low-voltage secondary circuit. The fake device is failing here. The image above show the transformers after the primary windings, and the insulating tape has been removed. The secondary coil is visible. At first glance, the wires look similar, but there are significant differences. The original charger (left) has a triple insulator, while the imitation (right) is only insulated by a thin varnish on the wire. The triple insulated wire is a crucial safety measure. Even if there is a leak in the insulating tape or the wire harness, the high voltage can still be isolated. Also, pay attention to the black and white insulation of the wires from the transformer. The only thing separating the high tension from the secondary winding in the imitation charger is the insulating tape.
Comparison Of Power Output And Quality Of Original And Fake iPad Chargers
In the previous articles, the original Apple iPad charger has been thoroughly compared with a fake one. In this article, another characteristic of the two chargers will be analyzed. An important but unseen quality of chargers that should be considered is the power output and the voltage quality. When the outputs of the chargers are measured in the laboratory, the fake device has two main problems. First, the simulated device can only deliver 5.9W instead of 10W as stated on the label. Second, the output voltage of the imitation has a lot of noise and full of spikes.
The voltage-current graphs above show how the iPad charger (on the left) and the imitation charger (on the right) perform with increasing load. The graph of the original charger goes farther to the right, indicating that it can deliver much more current. According to the measurements, the original charger’s power output can reach up to 10.1 Watt and the counterfeit up to 5.9 Watt. This power difference means that the original charger charges the iPad twice as fast. The other thing to note is the Apple charger’s frequency spectrum is smooth and thin, and the fake one is spread out. This graph means that the output of the counterfeit device has a lot of noise and poor quality.
The other pair of graphs gives an idea of the quality of the power output. The lower limit of the yellow spectrum of the fake device is also wavy, which is due to the 100 Hz (120Hz) ripple voltage coming from the network.
The orange chart also shows the frequency spectrum of the output. The lower, the better. The rise also indicates the voltage quality is exponentially worsening. The fake device’s frequency range is usually higher, and there is also a dangerous jump around the switching frequency. This data indicates that the power output of the counterfeit device is worse over the entire frequency spectrum.
So, does the quality of the power output matter? Poor quality output affects most touchscreen functions. Attempts from a bad power supply cause the screen to run erratically. If you have problems with the screen when you plug in the charger, it is probably the charger itself. Poor power quality can also damage electronic devices in the long run. That is why it is not recommended to charge iPad and iPhones using counterfeit chargers because their quality is highly questionable. Apple went through the trouble of designing more complicated charger so that their chargers can produce stable and better quality power output.
Internal Structure Of An iPad Charger
There is more than you expect in a transformer. In this section, the transformer of the genuine charger will be completely disassembled and examined.
The first picture above shows the first layer underneath the yellow insulation band. The ferrite is surrounded by a copper ribbon to ground the core. When you remove the ferrite core, other insulations also appear; which is the double-insulated primary winding. The input voltage goes to this winding.
When you remove the primary bandage and a few more insulation bands, you can see the three-wire feedback band. This winding provides both feedback and supply voltage to the control integration. In the photo, this winding is seen as being opened around the transformer. After removing some of the insulation band again, the secondary winding begins to appear. As mentioned earlier, the secondary winding is triple insulated, and there is also extra insulation at the output points of the transformer. The final insulation layer (pictured on the right) contains a copper foil. This copper reduces high-frequency interference.
Finally, the bottom of the Flyback transformer of the iPad charge (top). Here is the other half of the primer. Primer winding is a much more expensive way to do in two layers, but with a much better matching of magnetic fields, hence a much better transformer.
On the other hand, the quality of the fake transformer is much worse. There is a feedback coil, a secondary winding, and a primary coil separated by an insulating tape. Copper foil was not used in the transformer of the fake device to save production cost. The manufacturer does not use more expensive multi-wire straps that are available in the original. As mentioned above, the secondary windings are not wrapped with triple insulated wire, but only with copper wire. This build is a severe security issue, of course.
What are the differences between iPad charger and iPhone charger?
The iPad charger is considerably larger but has double the power than the iPhone charger. The iPhone charger (below) contains two circuit boards in just one inch-cubic volume, which is an impressive engineering achievement. Both iPhone and iPad chargers include a Flyback switched-mode power supply circuit, but the feedback mechanisms are different. The iPhone charger is more impressive when it comes to design because a similar circuit is fitted in a much smaller volume.
Apple’s charger, when compared with others, is expensive, but the price is matched with a quality product. You should never use fake chargers because they have low quality and dangerous to use. There are good quality chargers though from third-party manufacturers, and some are even better than Apple’s. Another cheaper option to save some money without sacrificing quality and safety is to buy genuine used charger online.
Apple’s profit margins on such devices are very high. Even though they dropped the price from $29 to $19 for download, the price is relatively high compared to high-quality chargers from other reputable brands. Regardless, the iPad charger is an impressive engineering work and an interesting circuit design. In fact, the fake charger is also very impressive to its right. It’s difficult to understand how they can produce a fake iPad charger and sell it at such a low price. In the end, the result is almost always you get what you pay for. Although the two chargers are very similar from the outside, the interior appearance and quality are very different.