SMD cap value needed

[techbrat]

hi forum,

can any one help me find the value of a large flat SMD cap

it reads these numbers on the cap from top down

R36
249
H76

[budm]

Re: SMD cap value needed

Can we see the pictures of the cap?

[techbrat]

Re: SMD cap value needed

picture attached

[stj]

Re: SMD cap value needed

that's an inductor.

[techbrat]

Re: SMD cap value needed

that's an inductor.

oh ok,

do you know how to find the values?
I think i need to match up the inductance, current ratings and resistance to replace it.

i would guess the 249 means Inductance 2.4µH

[stj]

Re: SMD cap value needed

why do you need to replace it?
if you say it's shorted i'm going to LOL

[redwire]

Re: SMD cap value needed

I figure the R36 denotes 0.36uH for high-current low profile (flat) inductors.
You would need the manufacturer's name to nail the part i.e series 249. My guess H76 is the date code/plant ID. Beyond this, look to the app note for the IC driving this inductor, for inductor part numbers.
These parts don't fail unless cracked/chipped or overheated.

See:
http://www.nec-tokin.com/english/pro...nductors_e.pdf
http://products.sumida.com/ProductsI...=104CDMCC%2FDS
http://products.sumida.com/ProductsI...p?type=CDBH128

[techbrat]

Re: SMD cap value needed

shorted. reading very, very small resistance, less than an ohm

it got wet

[stj]

Re: SMD cap value needed

it's supposed to look like that - it's a coil of copper wire!

[techbrat]

Re: SMD cap value needed

it's supposed to look like that - it's a coil of copper wire!

it shorts out the board when on, when off the board is not shorted

guess it could be something else beyond its circuit then. cant seem to see anything broken

probably one of the small smd caps behind it then

[stj]

Re: SMD cap value needed

if it's off the board, meter the resistance between the pcb pads.
also, what's the resistance of the inductor off-board?

[techbrat]

Re: SMD cap value needed

if it's off the board, meter the resistance between the pcb pads.
also, what's the resistance of the inductor off-board?

inductor is 0.8,

im guessing one of the tiny smd caps is the short now.

[stj]

Re: SMD cap value needed

if it's part of a switching psu circuit then there may be a diode involved.

[budm]

Re: SMD cap value needed

Good clear pictures of the whole board? What is this board used in?
Probably may have shorted SEMI on the board.

[techbrat]

Re: SMD cap value needed

Good clear pictures of the whole board? What is this board used in?
Probably may have shorted SEMI on the board.

PC motherboard: there is nothing visually damaged,

a block of caps after the inductor leading to the cpu is still shorted when i pull the inductor off.

and if I also pull the cpu off, the rest of the board is not shorted, so i see the area where the short should be at.

Might be several shorts

I guess I should have checked that earlier before posting, Really, I cant think too fast, it takes me time to think everything thoroughly and its hard to focus around here

thanks for teaching me what an inductor is by the way, i thought it was a tantalum cap at first, but now i see those on the bottom. *not very big ones*
but this is making sense now