Author Topic: How did this even get through QA? (Chinese boost converter)  (Read 880 times)

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Online bd139

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How did this even get through QA? (Chinese boost converter)
« on: December 02, 2017, 11:03:33 am »
Decided to order a bunch of stuff from China just to see if it will indeed handle the outlandlish claims that are made on the auction bodies.

Item number one arrived today, which is a little boost converter. Supposedly if I chuck in 5V @ 1A, it'll kick out 12V @ 370mA out switching around 1MHz. That's a respectable estimate compared to some. I've seen things like this advertising 5A out  :palm:

Well it would if the output filter was actually attached at one end:



Only one side is actually a good solder joint. The other end, not pictured is floating.  :palm:
« Last Edit: December 02, 2017, 11:05:16 am by bd139 »
 

Offline Kilo Tango

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Re: How did this even get through QA? (Chinese boost converter)
« Reply #1 on: December 02, 2017, 12:41:38 pm »
and that cap next to the connector has been knocked over physically breaking both joints
Maybe chinese don't actually test stuff, they just build it and ship it.

Ken
 

Offline Specmaster

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Re: How did this even get through QA? (Chinese boost converter)
« Reply #2 on: December 02, 2017, 12:43:33 pm »
Nope, thats just a "floating" output.  :-DD
Who let Murphy in?

Brymen-Fluke-Solartron-HP-Thurlby-Heathkit-Thander-Tek-Extech-Black Star-GW-Advance-Avo
 
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Offline retrolefty

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Re: How did this even get through QA? (Chinese boost converter)
« Reply #3 on: December 02, 2017, 12:50:30 pm »
Well how does it work after you repaired it?

 

Online bd139

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Re: How did this even get through QA? (Chinese boost converter)
« Reply #4 on: December 02, 2017, 12:59:47 pm »
Repaired (badly) and tested. It's quite decent. Looks like it passed because the cap was on the input side of things. It's a 10uF MLCC for ref. I measured it out of circuit.

I think it had lifted before the solder had returned to solid and it was just tombstoned there. Joint wasn't actually broken

I can pull 6W out of it (500mA at 12V) for 8W in whilst blasting the shit out of it with a hairdryer. Still going strong even if the breadboard is melting (I used a crap one just for this test).

Tentacle monster testing it:



Output:



Not bad for under £1.
« Last Edit: December 02, 2017, 01:02:22 pm by bd139 »
 


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