Portable Fan / Radio / Light / Powerbank
This multifunctional rechargeable fan from Tough Mama has been pretty good. However, it’s not able to charge and kept the battery drained recently. There were popping noises on the unit whenever I plug it in and there is certainly something wrong with it.
Disassembly
Disassembly was pretty easy but take note that the screws were treated with Loctite. A little bit of force is required to undo the seal but it is easier than undoing clips by prying.
The Cause
One terminal at the voltage inputs on the power supply board was burnt. A bad solder job is probably the cause for this kind of failure.
The Fixed Board
The solder mask was sanded down and both terminals were resoldered and given plenty of lead for better contact.
Other Pictures
The supply board is a typical switch-mode power supply with 220V AC input to 7.8V DC output.
The main board seems to be a single layer copper PCB.
The PCB is tightly packed, a more thorough analysis on this board might be nice.
Here’s the specifications for the battery pack they used.