Some time ago I bought a clip-on lamp to use on my workbench. It was a bright white LED lamp that created no noticeable RF interference and it had a bendy, segmented neck, so I could angle the light where I needed it. It was ideal, although now and again it would dim a little before returning to full brightness. It has an IKEA 3.5v 600mA Power Supply Adapter model ELP003C0600PB, which provides 600mA DC at between 2.5 and 3.5v.
One evening I was repairing a radio and the lamp dimmed before I heard a ‘crack’ and the lamp went out. A quick look at the power supply and I saw a black burn mark on the inside of the case above the middle of the PCB, which is visible through the case.
Replacements are available on eBay for anything up to £25, so I thought I’d have a go at repairing this one.
WARNING: DO NOT attempt to repair this unit if you are not competent to do so. There are mains voltages inside this unit which can kill you. If you don’t repair it properly, you could also cause a fire. Should you decide to repair your unit, you do it entirely of your own volition and at your own risk.
There is a Torx screw in the middle of the mains supply end of the power supply. Once you remove this, the case holding the PCB can be slid back and out. You will need to carefully split the two case halves; they are either lightly glued or ultrasonically welded together.
Once apart, you will be able to see the circuit board. On mine the top of the 7 pin IC in the middle of the board had been blown off; you can see it, it looks like an ordinary 8 pin IC with a missing leg.
There is a small PCB fuse, mine looked like a small tubular resistor, but it’s the small black rectangular component, right between the blue and brown wires on the photo. Mine was open circuit. Carefully desolder and remove the old IC and blown fuse. Under the board you will find a bridge rectifier and some diodes…check these and examine any other components for signs of damage or burning.
If your supply is otherwise okay, you will need to order an LNK364PN Energy-Efficient Off-Line Switcher IC and a 250v T1A time delay PCB fuse. I bought three fuses and one IC from the same UK supplier on eBay for £6.
Once you have fitted them, check your work, then reassemble the unit before testing it. Mine now works better than it did when new…and it’s another item that won’t go to landfill.