How do I find out what type of SMD I've got?

Chat about pick and place machines, reflow ovens, assembly techniques and other SMT tips & trix

Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.
Locked
User avatar
rowan_bradley
 
Posts: 2
Joined: Tue Jan 28, 2020 11:05 am

How do I find out what type of SMD I've got?

Post by rowan_bradley »

I've got an 8-pin SMD that I must have bought some time ago, but now I can't remember what it is. Is there a way to find out? It doesn't seem to have any part number written on it, although there seems to be something written on the underside of the chip, but it is obscured by the earth contact. The package seems to be transparent, which implies maybe it is some sort of optical device? Attached are pictures of the top and bottom of the device.

Thank you - Rowan
Attachments
SMD 221109 A.jpg
SMD 221109 A.jpg (112.31 KiB) Viewed 1366 times
SMD 221109 B.jpg
SMD 221109 B.jpg (140.15 KiB) Viewed 1366 times

User avatar
adafruit_support_mike
 
Posts: 67391
Joined: Thu Feb 11, 2010 2:51 pm

Re: How do I find out what type of SMD I've got?

Post by adafruit_support_mike »

That's definitely unusual.

My first guess is that it's a marketing/technology-demonstration sample. Silicon is photoelectric, so having the whole die exposed to light would make it unreliable. If it is a functional device, it's probably designed to live in a dark environment.

Without a part number it's nearly impossible to guess what the device is. One trick to try reading the number on the package is to lay a piece of Scotch tape on it. The tape will adhere to the flat surface but the etched channels for the characters will be a bit darker.

Beyond that, the only clues are the wires bonded to the pads: each wire can usually handle up to 500mA, so the pads with two and three wires are probably made for higher current.

The gold-coated array at the end does look like some kind of optical sensor, but there don't seem to be many sense elements. Given the way the shapes are offset, and the implied power levels for the pads with extra bond wires, I can offer a wild guess that it's an autofocus controller for a camera lens motor.

Locked
Please be positive and constructive with your questions and comments.

Return to “SMT (Surface Mount Tech)”