What is it? (electronics part quiz =)

[wotnot]

It's thin and flexible ;




It measures 100m wide by 60mm high by 0.5mm thick, and weigh 2.5grams -- the front side is dark grey, and has a self-adhesive backing covered by wax paper (like a sticker);



On the back side, a 1cm square has been cut out of the wax paper, exposing the self-adhesive backing;




I know what it is, but does anyone else here?

[answer coming this Friday if nobody else can guess/identify what it is B^]

[hoe]

Wireless charging element

Sent from my SM-T355Y using Tapatalk

[wotnot]

Wireless charging element

Has only 1 contact point and therefore cannot be used as a battery charger (every incorrect try yields a further clue =)

[shred]

The cover for the magnetron opening in a microwave oven?

[lsemmens]

A new flexible display.

[wotnot]

The cover for the magnetron opening in a microwave oven?

Not part of a microwave, and it works at shorter wavelength

[wotnot]

A new flexible display.

Does not operate in the visible light spectrum =)

[lsemmens]

AN IR sensor or the like.

[wotnot]

AN IR sensor or the like.

Would emit some IR when in use, but doesn't sense anything

[Uncle Fester]

A radiator/antenna/capacitive coupling for frequencies higher than 2.3GHz (except visible spectrum) that also radiates heat loss.

[Uncle Fester]

To squeeze out even more clues a second suggestion:
A shielding device for frequencies higher than 2.3GHz (except visible spectrum) that radiates heat loss.

[kolithawick]

RF shield in smp transformer.

[wotnot]

A radiator/antenna/capacitive coupling for frequencies higher than 2.3GHz (except visible spectrum) that also radiates heat loss.

It does indeed radiate heat, and the frequency component is an intrinsic part of that operation.

[wotnot]

RF shield in smp transformer.

It has no shielding function, and is pretty much transparent to RF energy

[wotnot]

To squeeze out even more clues a second suggestion:
A shielding device for frequencies higher than 2.3GHz (except visible spectrum) that radiates heat loss.

Ok, I can squeeze you out more clues....

I discovered this in an industrial computerized plasma cutter rig, to wit, in the TFT touchscreen display for said device (but I have seen this technology in other devices)

customer complaint: display goes black after about 5mins of operation, but power indicator LED on display remains lit. Turning display off/on restores image for a few minutes before going blank again (this is how they'd been using it for the last few months, because manufacturer was wanting $700 for new VDU)

[Uncle Fester]

Ok, I can squeeze you out more clues....

I discovered this in an industrial computerized plasma cutter rig, to wit, in the TFT touchscreen display for said device (but I have seen this technology in other devices)

customer complaint: display goes black after about 5mins of operation, but power indicator LED on display remains lit. Turning display off/on restores image for a few minutes before going blank again (this is how they'd been using it for the last few months, because manufacturer was wanting $700 for new VDU)

Damnit, I had a component for a capacitive touchscreen display on my mind but the > 2.3Ghz didn't make sense.

Lsemmens was at least a bit on the money.

[wotnot]

Damnit, I had a component for a capacitive touchscreen display on my mind but the > 2.3Ghz didn't make sense.

Lsemmens was at least a bit on the money.

Actually, you're a bit closer than you think. I can imagine out in the real world, someone working on something like this (that didn't know what's going on) could pop the back cover off, have this thing fall out, pick it up, examine it, and go "Just wtf is this? Some sort of sticker or something? Whatever, it's not gunna be the problem"....toss it in the bin. That, would be the wrong response -- the correct observation would be "Hmmm, what was this attached to?", and go searching for that location.

[wotnot]

As one might guess, the cause of the display going black was the backlight controller winking out ~ a closer inspection found not only the backlight was going out, but the TFT wasn't producing images either.

At the top of the panel was the controller PCB (foreground, green PCB);



The small IC to the left is the backlight inverter -- the larger IC center of image is a LCD-TFT PMIC chip ...this thing gets hot, and must have over-temp protection ; when it shuts down, it also disables backlight inverter.

So I grabbed some CA adhesive and reattached the heatsink to the PMIC chip, and that fixed the issue;

[Uncle Fester]

Like almost everything these days, cheapskate design to fail.
One would expect for something expensive like a plasma cutter to use proper heat sinks firmly attached and not just a bit of foil hanging in there with a bit of sticky stuff.

[wotnot]

Like almost everything these days, cheapskate design to fail.
One would expect for something expensive like a plasma cutter to use proper heat sinks firmly attached and not just a bit of foil hanging in there with a bit of sticky stuff.

Machine itself bears the 'Made in PRC' sticker =)

The item itself is pretty much described as 'High Thermally Conductive Expanded Flexible Graphite Heat sink' -- it can be bought in various guises, with/without copper backing sheet, in any size/shape you can think of.

As a thermal management technology, (surprisingly to myself), it actually works quite well ; the shortfall is that adhesive used to affix it ...as intimated above, this is by no means the first time I've seen these come unstuck.