Component name on a laptop motherboard.

[nagper]

Sorry for the lame question... I have got an acer aspire 1670 laptop motherboard. Could anyone please tell me the name of the component on the picture below under the red arrow?
resistor? diode?

https://picasaweb.google.com/lh/photo/EwW_EhV_Vqeoit6lwXqvAphKRpdbdZMR2g80XAskZZg?feat=directlink

Thank you!
Peter

 

[RWJ]

Never done any surface mount stuff. The electronics I know things look like they're meant to..

It's not a resister as you can see resisters (and their value) also on the board.

My personal guess is a capacitor, diodes tend to be black.

 

[topquark]

It's either an SMT resistor or capacitor, how is it labeled? PR or PC, I can't tell from the pic.

 

[nagper]

Thanks for the quick reply.
It's labeled PC.

Is it a capacitor then?

 

[topquark]

Yes, most likely a decoupling capacitor for one of the chips. You'll find labelling for most smt chips on the motherboard somewhere and diff manufacturers use diff conventions, but usually similar.

 

[nagper]

Yes I think there is a label saying PC161.
Do you think the number is just for counting the pieces or is it 161 nano or micro Fahrad?
As I know I cant measure them with a simple multimeter

 

[topquark]

No not for capacity, it's purely to uniquely identifying a component on a motherboard ... bears no resemblance to it's capacity (unless coincidental).

 

[nagper]

OK, thanks for the answers!
I'll try to get it measured with someone.

 

[topquark]

You may find getting someone to measure it a bit of a challenge, you'll need someone with an ESR meter that can be used with smt components. You could try one of your local electronics companies, if you have any in your area.

 

[nagper]

You may find getting someone to measure it a bit of a challenge, you'll need someone with an ESR meter that can be used with smt components. You could try one of your local electronics companies, if you have any in your area.

OK, thanks!

 

[topquark]

Sorry when you say measure it, do you mean see if it's working or what it's capacitance is ? ... if it's the latter then it's a capacitance meter that's needed. The ESR is normally for fault finding.

 

[telectrix]

and if you try and measure it, youi'll read everything that's connected round it, parallel paths etc. you can't measure it without first removing it from the board.

 

[topquark]

Spot on Tel, the ESR will work fine with comps in place, capacitance won't.

 

[mozzo]

Back in the day when discreet components where going out and surface mounting tech coming in, the surface mount boards basically had little servicable components. The capacitors and resistors basically have no indentification of their values unless you had a circuit diagram for reference and it would be difficult to impossible to get replacement surface mount resistors and capacitors. The big cost is the CPU and other replaceable components which would be mounted on a ZIF socket so I would imagine any small component failure would render the board beyond economical repair. Component level repair on such boards became a thing of the past and it spelled the end of a triving component level repair market at the time.

 

[topquark]

It's unusual for one of the smt ones to fail, more usual for the large electolytics to go, often in the PSU (cause of many failures). Most of the more modern motherboards have started to use solid capacitors now for better reliability (circa 10 years claimed by some manuf).