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what diode do i need to protect a USB flash drive? Answered

well, lately i've shorted an USB port, and a USB flash drive, i know, i seem hazardoes :D
i broke the USB drive by changing the voltage and GND (no questions on how please) so it broke.
when asking what i could do to repair it, it was buy a new one and transfer the control chip, wich is impossible for me :D
but, someone else said that manufacturors (i know i spelled that wrong >.<) dont put in diodes anymore...

what i need to know is, what diode do i need?
i need specs (maybe an example) not where to buy them, since i live in holland (netherlands, the dutch, uve heard of us cheeseheads) and wont pay €10 shipping fee for a €1 diode...
i need something that wont (or minimally) interferes with the VCC from a USB port (5V at 5mA) and still makes the power go one way, at SMD size.

btw, im not good with diodes, only the light emitting ones :)
wait a sec, will a low rated SMD led do the trick? or will the resistor needed for that make the power to low?


Use a 1N4001, in surface mount, in series with the 5V line  and see if the drive will still boots. There's a fair chance the 0.6 V drop of the diode will screw the boot process up. Putting it in anti-parallel might work, but you'll be relying on the USB port to shut down before it fuses the diode. 

i can only buy those at normal trough hole size.
but what about LED's? will that work to and add a light as a bonus?

so, no led.
and that diode might be to much also :D

no other options?
like putting a diode between the VCC and ground so the when i insert it wrongly, the power goes directly to GND, thus protecting the flash drive?
but what about the USB port on the PC? will that burn out?

I expect PC USB ports to be smart enough to shut down.

'course, you could always measure things before you plug them in.....

well, mine wasnt, and i know the led+resistor isnt the problem, i just made the connectors to big.

Surface-mount, on a USB stick (Deja-vu, why?) - to protect against getting your wires the wrong way around?


Trying to protect things from you breaking them by soldering bits into them is hardly likely to work if you can break things by other similar DIY. You need to do things right. How about rigging a simple LED to test it before plugging something expensive in there? "USB light" in the search box should do it for you.

Data lines are less likely to fry things, but take good care on the construction.


Much better solution.  Led's are seldom broken by reverse voltage.

and the resistor? wouldnt that cut to much power for the USB drive?