Components designated "SK"?

Hi all,

Can anyone tell me what an "SK" component is?

On a hard drive controller board, there are several of these things.. "SK1", "SK2", etc...

They are SMT devices about 5mm long by 3mm wide by 2mm tall. They look like they are made of maybe quartz (translucent clear/white look) and there are three layers of the "quartz" stacked on top of each other and in parallel. They have two terminals (one on each end).

Anyone know what these things are? I Googled (or tried to) and didn't come up with anything meaningful.

Thanks!

-- Roger

Could you post a picture?

Socket?

Sure!

Intriguing - could be a socket (you'd need to the other side of the board).

Judging from the image and the image of the other footprint it looks like some kind of resonator... 2 different case styles/purposes But still from that white SK2 part and there are at least 2 caps visibly connected so my thought about a resonator. It's not a diode or spark gap which might have similar designators (Surge arresters of both gaseous or semiconductor types 'might be marked that way). I've serviced a lot of test equipment and seen things similar but not identical to those parts/footprints.

Bob

The metal pattern does look fuse-like.
The presence of power supply sockets or high power devices like power transistors nearby might clinch it.

krupski:

[quote author=Tom Carpenter link=topic=126081.msg947954#msg947954 date=1349637324]
Could you post a picture?

Sure!


[/quote]

My web blocker blocks this. I wonder why... gunsnet.net Hmmm...

The single thing that stood out to me was the size of the traces... Protective devices usually have shorter and Much wider traces, those appear to be 8 to 10 mil traces or inductors in series with the protection. I really don't know what the parts actually are I just tried to figure out "IF" those were protection devices than it would be a mistake to use small "wires" (PCB Traces) to provide the interconnection. These are part of "Basic" design rules for PCB layout and my reasoning in "reverse" engineering the subject.

Bob

JoeN:
My web blocker blocks this. I wonder why... gunsnet.net Hmmm...

Could you tell me which web blocker you are using?

krupski:

JoeN:
My web blocker blocks this. I wonder why... gunsnet.net Hmmm...

Could you tell me which web blocker you are using?

It's a corporate blocker - WatchGuard. It blocks it due to "weapons" which I guess is proscribed here at the copper mine. It blocks adult stuff and "hate" and other categories deemed to be detrimental to productivity, including eBay (but not Amazon). Sometimes it makes really stupid mistakes. It has a Las Vegas newspaper blocked due to "adult" - maybe there is a section on there on topless shows or something.

Sorry for delay :smiley:
Anyway that component is a vibration sensor. The IC uses it to compensate any kind of shock or vibration.

JoeN:
It's a corporate blocker - ... Sometimes it makes really stupid mistakes.

Oh, only "sometimes" eh?

This is the crucial danger when some loony politician (or pit thereof) determines to "filter" the Internet.

Oh wait - the UK!

Piezoelectric shock-sensor. Moves the heads to a safe place on the platters, and probably sets a bit in the chipset that tells the manufacturer that you invalidated your warranty.

http://www1.futureelectronics.com/doc/MURATA/PKGS-00LD-R.pdf

// Per.

shock sensor
www1.futureelectronics.com/doc/MURATA/PKGS-00LD-R.pdf

shahroozmufi:
shock sensor
www1.futureelectronics.com/doc/MURATA/PKGS-00LD-R.pdf

And you found it necessary to revive this old thread to post the same link as I posted Feb, 9?

// Per.

Zapro:
Piezoelectric shock-sensor. Moves the heads to a safe place on the platters, and probably sets a bit in the chipset that tells the manufacturer that you invalidated your warranty.

http://www1.futureelectronics.com/doc/MURATA/PKGS-00LD-R.pdf

// Per.

Sorry this reply took so long but your info was posted 3 years after I initially asked, so I had long since given up on the question and never saw your post until now.

Anyway, I’m 100% sure you nailed it. The parts are designated “SKn” which makes sense… SK=shock. And, one of the links you posted mentioned that the hard drives which use these usually mount 3 of them at 45 degree angles to each other (again makes sense to determine which direction a shock came from)… and indeed the PC board photo I posted is from a hard drive and they are at 45 degrees to each other.

So, besser spät als nie, Ja?.. thank you for the reply and the info… and a Karma++ for you too.

Thanks again!