smoked my shark

[07accordEX]

=( ok today i accidentally reversed the positive and negative for the inputs and saw the smoke :mecry:

so... to prevent this from happening in the future, could I jsut add a diode between the input wires and be done with it?

 

[VanIsleDSM]

If you do, you'll also be done with 0.5-0.7V, or wasting around 1.2W with a 2amp input.

Better off to just double check what you're doing.

 

[VegasF6]

Depending on the voltage's you are using, it can be done though. Here is a solution offered for the Zetex C310 circuit.
http://www.zetex.com/3.0/appnotes/design/dn78.pdf

 

[CM]

If you must use a diode, use a Schottky. It has a lower Vf.

 

[yellow]

check the Shark.
If the main IC does not features any optical damage (usually there is some kind of silver "bubble" somewhere, or some kind of deformation).

If there is NOTHING, check that small resistor at the left, where that 0.75" 19.1 mm DIA arrow points to.
I once reversed power by accident and that resistor smoked off, but when changed everything works as before


http://theledguy.chainreactionweb.com/images/Shark_wiring.gif

 

[07accordEX]

hmm, i do see a small pitted hole in it, so i guess its dead but i did check the resistor and theres no power going to it, but im guessing thats because its dead

 

[VanIsleDSM]

There's always a small indent in IC chips, it's there to tell you which is pin#1. So if it's on one of the corners and looks manufactured at all.. then it is.

There's a good chance the majority of the board is fine, and only 1 component is toast, like stated above. If you've got a camera I suggest taking a closeup of the board and posting it. If there was smoke it should be pretty easy to identify what has gone bad.

 

[07accordEX]

its more like in the middle, but it doesnt seem like theres anything wrong with it, i jsut know it doesnt work

and before there was 26v goign through the string of led's, now its only 12v and im running it on 3 liion cells

heres the picture

and the black wire was resting on the chip before, so mayb the chip burnt the wire aswell?

 

[VanIsleDSM]

Yeah, unfortunately it looks like the chip has seriously overheated and melted part of that wire. I think you're gonna need a new shark.

 

[07accordEX]

yeah.. *sigh this is an expensive hobby twenty dollars here and there

well thanks for everyones help