Screens are one of the first things to get damaged when you drop your MacBook.
You can follow me on Twitter and find out about my new articles.įor those who care about the component details, the I've written a bunch of articles before about chargers, so if this article seems familiar, you're probably thinking of an earlier article, such as: While counterfeit chargers are much cheaper, they are also dangerous to you and your computer. It also ignores safety requirements with less than a millimeter separating you and your computer from a dangerous shock. The counterfeit has a much simpler circuit that provides poorer-quality power. But on the inside, the difference between the counterfeit and real chargers is clear. Until I opened it up, I wasn't completely sure that it was counterfeit. This counterfeit Magsafe charger is convincing from the outside, with more attention to detail than most. The output of the counterfeit charger has large 2.7V noise spikes when a transistor switches internally. The additional parts provide better power quality and improved safety in the real charger this is part of the reason genuine chargers are significantly more expensive. The two boards are in totally different worlds of design complexity.
#Apple stickers for macbook pro inner side full#
As you can see, the counterfeit has a simple circuit board with just a few parts, while the genuine charger is crammed full of parts. The photo below compares the underside of the counterfeit 45W charger (left) with a genuine Apple 60W charger (right). However, the pin is just for appearance and is not connected to anything.
The counterfeit charger has a metal ground pin (unlike other fakes I've seen that have a plastic pin). I didn't disassemble the transformer, but I expect it also lacks the necessary insulation. The counterfeit charger lacks extra insulation, except heat-shrink tubing around the fuse and fusible resistor. The heat sink is basically a giant conductor between the two sides of the circuit, with only small gaps separating it from active parts of the circuit.Īs well as having large creepage and clearance distances between high and low voltages, genuine chargers also make extensive use of insulating tape for separation. The second safety flaw is the heat sink that provides cooling for the input-side MOSFET and the output-side diode. It shouldn't take much additional effort to make the boards safer. Except in the smallest cube phone chargers, they aren't fighting for every millimeter of space. They use simple, low-complexity circuits so the circuit board layout should be straightforward. I'm puzzled as to why counterfeit chargers never manage to have sufficientĬlearance distances. This is why you shouldn't buy counterfeit chargers. The counterfeit MagSafe charger has a dangerously small distance between the low voltage side (top) and the high voltage side (bottom). A real Apple charger is packed full of complex circuitry, while this charger had a fairly low density board that implemented a simple flyback switching power supply. This raises the risk of burning out your laptop if you plug the connector in crooked or metallic debris sticks to the magnet.Ĭracking the charger open with a chisel reveals the internal circuitry. The counterfeit charger, on the other hand, omits the microcontroller circuit and simply outputs the full voltage at all times. This is a safety feature of the real charger that reduces the risk from a short circuit across the pins. (Details are in my Magsafe connector teardown article.) Only when a microcontroller inside the charger detects that the charger is connected to a laptop does the charger switch to the full output power. Since the charger is rated at 14.85 volts, this may seem normal, but the behavior of a real charger is different.Ī Magsafe charger initially produces a low-current output of 3 to 6 volts, so shorting the output should not produce a spark. I measured 14.75 volts output and got a spark when I shorted the pins. The seams in a counterfeit Magsafe power supply are a bit asymmetrical.Ī problem showed up when I plugged in the charger and measured the output at the Magsafe connector.
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