Powerless: Fake iPhone charger and cable
I decided to open the fake charger and look inside. It was, dare I say, a popping experience.
Opening the case required an X-Acto knife, one of my father's favorite tools. Figure 2 shows the electronics. There are two boards. One is the main power supply, the other is a USB connector board with a 470µF electrolytic capacitor connected across the USB +5V and return pins.
Figure 2. Inside the fake iPhone charger.
Looking around, I found several examples of poor soldering and at least two broken connections. Figure 3 shows the underside of the main board. The poor soldering and component insertion are clear.
Figure 3. Poor solder connections could be causing the lack of output.
Figure 4 shows more poor component insertions. The four-pin component could be a filter or circuit-protection device. It's connected across the AC mains lines and the output side is marked with plus and minus indications.
Figure 4. Look at this component placement.
You can see a bad connection in Figure 5. The logical thing to do has to repair the bad solder connection, using my new LED soldering iron, right? That's what I thought. So, I repaired the bad connection and applied AC power.
Figure 5. More poor component placement.
I then used my meter to check the output voltage. Now before going on, look back at Figure 2. Do you see that 470µF capacitor on the far left next to the USB connector? Well, my finger brushed it and it was hot, very hot. Next, I heard a kind or whirring sound and then pop went the capacitor. The bottom of the package popped off. See Figure 6.
Figure 6. A 470µF capacitor pops open.
But then, I noticed another broken connection on the connector board (Figure 7) so I fixed it. Just for fun, I measured the output voltage under no load: 5.2V. Go figure.
Figure 7. Another broken solder connection I had to repair.
Then I got brave and connected my iPhone to the USB connector. It didn't charge. Next time I visit a real electronic component store, I'll get a 470µF capacitor and try again.
Have you ever tried to repair a cell-phone charger? What's your experience?
This article appeared as two posts on The Connecting Edge, July 2013.
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