Good day folks. Someone came in with this picture frame today 
and it's shutting down the power brick...short on VCC obviously. What is NOT so obvious unfortunately is where the short is located. I took the little board off the chassis and soldered a wire to VCC (in place of a jumper resistor) which I connected to my supply and gently increased the current to about 2a....nothing's even warm. I let it cook like that for 5 minutes hoping some part of the board would get hotter than the rest, but I couldn't find it, at least not by the traditional method of palming the board and using iso alcohol. A thermal camera would be better suited for this, but forget about it: too expensive for too little use...any chance we can find a schematic ?
I posted some pics....I hoped it'd be a shorted FET or cap somewhere, but no: nothing, no heat at all, yet it's still eating 2a....really wish I could crank it more, but 2a is the maximum my bench supply at work can muster. I have a DPS ebay one at home which can pump harder than that, but I was thinking of something a little more extreme: UPS battery ? I WANT FLAMES ! It's 12v while the adapter is 19v, so it's not exceeding the rail, but it should still cause smoke to come out of something - provided the battery/wires don't give in....
and it's shutting down the power brick...short on VCC obviously. What is NOT so obvious unfortunately is where the short is located. I took the little board off the chassis and soldered a wire to VCC (in place of a jumper resistor) which I connected to my supply and gently increased the current to about 2a....nothing's even warm. I let it cook like that for 5 minutes hoping some part of the board would get hotter than the rest, but I couldn't find it, at least not by the traditional method of palming the board and using iso alcohol. A thermal camera would be better suited for this, but forget about it: too expensive for too little use...any chance we can find a schematic ?I posted some pics....I hoped it'd be a shorted FET or cap somewhere, but no: nothing, no heat at all, yet it's still eating 2a....really wish I could crank it more, but 2a is the maximum my bench supply at work can muster. I have a DPS ebay one at home which can pump harder than that, but I was thinking of something a little more extreme: UPS battery ? I WANT FLAMES !
It's 12v while the adapter is 19v, so it's not exceeding the rail, but it should still cause smoke to come out of something - provided the battery/wires don't give in....
Attached Files
The small cap which sizzled was indeed shorted. Removed it and it's now good as new. No trippy side-effects either. So that PSU really paid for itself by helping me identify that short 
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