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[Circuitbenders]

I've got a Korg Micro Kontrol controller thing which appears to have a serious problem on the power supply / connector board. Its drawing a LOT more current than its meant to be, even removed from the rest of the machine. Unfortunatley its all surface mount but i can see that theres an Texas LC139A Quad Comparator that has actually physically broken, presumably because it went pop. It also gets very hot when i do plug the thing into a power supply. I'm guessing there might be something gone short or not working quite right elsewhere but i'm not going to get anywhere without replacing this part.

The problem is, unless i want to buy hundreds i can't find a replacement anywhere. I've checked digikey, rapid, RS, farnell and anywhere else i can think of but theres nothing. I've also checked the TI site but this component isn't available as a sample.

Given the choise i'd rather not have to buy a new power board so does anyone know where i might replace this part? Is there likely to be a direct drop in replacement made by someone else?

[noystoise]

maybe a lm339 would be suitable? i usually see them in phones ive hacked up for parts. it should be a pretty common part.

[Circuitbenders]

hmmm, comparing the datasheets of the LC139A and the LM139A seems to indicate that they have very different characteristics, although i would have thought they were the same component by different manufacturers so maybe i'm reading it wrong. Not that i can actually get hold of either of them in less than industrial qantities as a surface mount IC or getting completely ripped off on ebay anyway, so thats not really an issue. The LM339 appears to have very different characteristics but its freely available just about everywhere  

The LC versions appear to be called 'micropower quad comparators' where as the LM versions are 'Low power quad comparators' and seem to be rated at higher voltages.

On the other hand i have got to that stage where i have about 20 different datasheets open at once and i have no idea whats going on, so i could be miistaken.

[Gordonjcp]

It won't be *that* different, and it's not like you can make it work any less...

[Circuitbenders]

Thats a good point, its not working at all now so i might as well give it a go. Theres another thing to add to the 'to do after christmas' list.

I'm thinking it might be easier to just buy a new power board, but whats the betting that Korg want about £50 for a replacement.