How to check if the LM2577T -ADJ P+ counterfeit or original

Papabravo

Joined Feb 24, 2006
12,978
They are likely to be manufacturing lot numbers and/or date codes. External markings are not a reliable way to tell much of anything about an IC, except if you can rub the marking off. Burning them out can happen for a variety of reasons. It often happens when somebody builds their first SMPS. These circuits can be tricky and often do not perform well on breadboards; they require careful layout on a printed circuit board.
 

GopherT

Joined Nov 23, 2012
8,012
Are you sure it is burned out - that chip also has a thermal protection, under-voltage lockout and current limiting to protect itself.

  • Output Switch Protected by Current Limit, Under-voltage Lockout, and Thermal Shutdown
 

Papabravo

Joined Feb 24, 2006
12,978
Are you sure it is burned out - that chip also has a thermal protection, under-voltage lockout and current limiting to protect itself.

  • Output Switch Protected by Current Limit, Under-voltage Lockout, and Thermal Shutdown
If the thermal protection has tripped then the chip is obviously being abused in some way. You might want to reconsider your circuit to understand why things are getting so hot. A schematic would be helpful or we could continue to take your word for things so we can fumble around in the dark for another week or so.
 

Papabravo

Joined Feb 24, 2006
12,978
I know it because it smoked out of the pin and then after that it won't boost voltage anymore and also the voltage shown on the volt meter shows lower than the battery can supply
Why would you think the chip would work after you let the magic smoke out? How about a schematic so we can help you troubleshoot the problem. You could of course continue to blame everyone else for your problem and you'll have to abandon your project for something simpler.
 

takao21203

Joined Apr 28, 2012
3,696
The pins should never be bent like this.
In fact the part is not designed for 2.54mm proto PCB.

There isnt so much business counterfeiting parts costing cents.
Just urban myth threads.
The part isnt particulary rare and still in production so who would want to counterfeit it?

Almost a good one as the free postage post offices in China (they dont exist).
 

gerty

Joined Aug 30, 2007
1,273
The pins should never be bent like this.
In fact the part is not designed for 2.54mm proto PCB.

There isnt so much business counterfeiting parts costing cents.
Just urban myth threads.
The
part isnt particulary rare and still in production so who would want to counterfeit it?

Almost a good one as the free postage post offices in China (they dont exist).
You mean like this??fake-caps.jpg
 
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