Control Board Component Replacement (Dummy Style!)

I have this circuit board


It appears to have blown a…component.
image

  • Any idea what this is? (I assume it’s like it’s buddy right next door)
    image
  • Any ideas where to get something like this (esp. right now)?
  • Anyone want to virtually hold a (effectively) 4-year-old’s hand in what it would take to replace this with a soldering iron?
    ** I have soldered things before (even SMC, though not necessarily “successfully”) that have worked out OK (I used to re-solder automotive relays with cracked cold-solder joints with fair aplomb, and other things from time to time but mostly through-hole type stuff…)

If I’m reading the numbers right, I think that thing says FR9110, and is a MOSFET
probably something like this?
https://www.alldatasheet.com/datasheet-pdf/pdf/167237/FAIRCHILD/SFR9110.html

Looks like I can buy 511 or more of them for $0.49 each…

Anywhere I can get, say, a tablespoonful for a $finster?

EDIT: and is it just 3 joints: 1 leg each at the one end, and the looong top? I think it is…

The best thing would be to try to find a picture of the undamaged component to get the part number. That does not look like a difficult unsoldering and resoldering job once you have the replacement part.

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In my rapid, cursory, and unprofessional opinion, this looks like a modern equivalent.

Worth taking a very close look at the rest of the board to make sure this isn’t just the result of another smaller short/failure.

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I’d say Mouser or Digikey. A week ago I would have said Tanner’s should have something compatible if you looked around. Depending on the topology of the FETS (how they are utilized) it may matter only that they are the “same” and not that they are specifically the exact ones you had.

If it were me? I’d use a hot air station, because those fills on the PCB look hard to heat with an iron, and I’d replace every similar looking part number FET on the board (within reason) to the closest compatible part I could find on Mouser. If it’s a matter of wall time not personal time spent, Mouser does a will call and they’re in Mansfield. Also, I’d look through the other smaller SOT23 type parts on that PCB, those may be the FET drivers and likely would have failed when that FET blew, and I’d have some of those on hand to replace as well. They should be cheap and available if you can find the part number for them.

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That’s these little guys?

I was referencing the smaller ones, but those too.

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Looks like the D-PAK packaging is a match looks-wise.
image

(from https://datasheetspdf.com/pdf/486977/FairchildSemiconductor/SFR9110/1)

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Paging @Raymond

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Mouser part #: 844-IRFR9110PBF

Whose yer daddy?

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Looks like Raymond agrees…
Still, at $8ish for shipping, buying just the one thing seems wasteful, but I don’t really NEED other “stuff”… Que lastima…

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You can pick it up on will call. But it might be worth your 8$ for shipping. Last time I picked up I had to call it in. They usually take an hour to get it ready.

Also another thing is you better have your drivers license with you. They won’t let you in otherwise.

Allied is about a 2 hour turnaround for will call but you can request it when you order online.

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Mouser has USPS as an option, for $4. You have to click “more shipping options” when placing your order. Probably less cost than driving there and back, plus your time. I find that USPS from Mansfield makes it to me in 2-3 days from the order.

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When/If you replace this, remember to use at least a minimum of ESD protection. FETs can be easily damaged by static electricity, far below what you can feel as a shock on a doorknob.

This looks to be an easy way to have some ESD protection wherever you’d like:

https://www.amazon.com/Velleman-AS9-Anti-Static-Field-Service/dp/B004XZQ30Y

If you can stand the purple/blue LED lightshow he has going on in this video, here’s a practical example of why ESD is bad, mmmkay.

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I’m still seeing $7.99 on that option:

And I’m still thinking that might be my best course of action, even if not strictly “worth it” accountant-wise…
It just makes my $0.60 component a $9.00 component instead… Still <$new/refurb unit (~$180ish min).
I think I have a line on a $50 used “good working” ( :wink: ) shipped to my doorstep, so that’s probably going to get my vote, but we’ll see. Also, depending on how good it works…I might still need this advice.

Thank you!

Do you not get an “Economy Shipping” option?

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I do not.
What you see in that screencap is all I see…

EDIT: Ah. One must create an account, verify it, and log in if one wishes to see the Economy Rate…
Hm…

Thank you!

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Remember you’ll want more than one. Spares will save you some headache when you go to solder.

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Indeed. I usually look at the qty 10 (or, for resistors, caps, etc. qty 100) and the price per item goes down faster than the qty.

On this one, I’d spring for qty 10. You can re-do the entire board, if you’d like, and have spares for other experiments, etc. Always good to keep some spare parts on hand (or … 10,000 spare parts, in my case).

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