Help identify a SOT23 part from a Fuel V10. - Printable Version
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Help identify a SOT23 part from a Fuel V10. - weblacky - 11-05-2021
Okay, I'm still probing what I think is the 5V and 12V lines on the V10 to try to find an open component that sits on BOTH lines. I may have found one...it's tiny (of course). One side is on the 12V rail and the other is on the 5V rail in some way or another.
I removed the component from the board and used my Huntron on it...the results...were...odd. Assuming this is it...which I don't think is right: https://www.diodes.com/assets/Datasheets/ds30330.pdf
There is no connection between pins 1 & 2, there is a diode connection between (I think, hard to know if i'm backwards from memory) 2 & 3, there is no connection between 1 & 3. The fact that half the path is dead, could indicate this is what I shorted out during my 1V injection test. It could ALSO have been the component that failed short originally to have the 5V line bring down the 12V through enabling something else...that's purely a wishful guess though.
The the marking layout is correct, but the values don't make any sense.
If you look at the picture I took, it clearly looks to me like it's say N ZERO S (N0S). It could be a 5, but it's too rounded to be a five to me, perfect for an "S" though.
No marking SMD code book I've tried has a N0 with a letter like that...nor an N "O" with any following letter.
I could also be reading it backwards? Because every letter can be reversed and still be correct, it could say "s0N", which "s0" is known SOT23 part and a diode..though no one claims to have an "N" at the end of an "s0" or "so". So still a problem.
So I'm stumped, if I can get a replacement part that I know is real, I can check it against this part, install it and see if anything changes.
I know a few of you members deal in this stuff/profession. Please take a few minutes to help me out on this. Even if there is a slim chance I can repair or get further along on this V10 card, it benefits us all, I'll share what I find on this effort.
RE: Help identify a SOT23 part from a Fuel V10. - Jacques - 11-05-2021
Sorry I can’t help ID the SOT package, though it does look like NOS and then 3M sideways as well? Hopefully somebody else with a V10 can help check on their boards.
You could also post your question on the BadCaps.net forum, I had some luck getting a SOT23 package identified there.
RE: Help identify a SOT23 part from a Fuel V10. - weblacky - 11-05-2021
I’ve gone ahead and posted a question on the stack overflow electrical engineering section here: https://electronics.stackexchange.com/questions/593752/help-identifying-a-failed-sot23-component-via-markings-nos
I hope I get some traction.
RE: Help identify a SOT23 part from a Fuel V10. - robespierre - 11-05-2021
"NOS" should be a N-Ch FET TN0200T: https://www.vishay.com/docs/70202/tn0200t.pdf
"NO" is the part code, "S" is the 26th work week, and "3H" is a lot code.
The normal configuration of a MOSFET is that there is a body diode from source to drain, with the gate isolated.
So your test showing a diode junction from 2 to 3 with no connection between either pin and 1 is normal for this component. A 3-lead component checker like the Peak DCA Pro can test if a MOSFET is conducting in response to gate charge; all that a 2-lead diode tester can tell you is whether the gate oxide has shorted, which is a common failure mode but not the only possible one.
RE: Help identify a SOT23 part from a Fuel V10. - weblacky - 11-05-2021
Yeah I also found that data sheet but the markings didn’t look exactly like the data sheet.
The 0 is small on the part, but large on the data sheet and they claim for W is a week code but they do not provide a sample or table of week codes, so there was no way to know if “S” is a possible value!
How confident are you on this, I get the bypass diode being consistent?
The data sheet says you can test it with a 2% duty cycle or less. My huntron can do that, setup will be a pain.
RE: Help identify a SOT23 part from a Fuel V10. - weblacky - 11-05-2021
Okay well the huntron says it does work (I can get it to turn on and off) so I'm reinstalling it and giving up. This is beyond me and even though there isn't much even on the card, the routing is very odd and cannot be visually followed due to all the layers.
I've resigned myself to stop wasting time until I have a duplicate card for comparison.