I have one tale to share ...
Recently repaired one Ansmann " Energy 8 " NiMH charger , its a lovely device well made ,
and it is an very smart one .

Still got injured at the 110/220 auto selector mini board , from bad AC supply of the electrical network.
The long story short , this board has on it an SHARP Photo-coupler PC817 ,
plus one mini transformer and few capacitors .
Plus the TOPSwitch-II ( smart transistor ) TOP 223Y .
In my case the TOP 223Y was blown , and there was no evidence of what it was ...
By searching on the net , for info , for the only one (second IC on the board) ( SHARP PC817 ) ,
found that it was used and in another 110/220 auto selector board, of another power-supply ,
called as Mastech HY5020E .
The TOP 223Y its an 30W one , the next TOP 224Y its an 35W one ...
And does the same job .
The point of my tale are , that those two parts SHARP PC817 & TOP 223Y , looks like they are always together , in those designs .
If you find the SHARP one on it , now you know what is the blown one !!

The latest Ansmann chargers , are great devices , about the damaged one , I got it damaged from Germany for just 10 EUR (ebay) .. 6 EUR was the cost for the TOP 224Y ( not Chinese one ) .
Got also as new the Ansmann " Energy 4 speed " .
And their digital battery tester " Energy Check LCD " ( with load ) .
All of them , fine products.
Here is , how the PCB of the 110/220 auto selector , looks like ... (Mastech HY5020E)
http://origin-images.rcuniverse.com/forum/upfiles/325364/Oj27986.jpg