Hard to read markings on chips

Thread Starter

SamR

Joined Mar 19, 2019
1,614
Seeing the stereoscope in the dream bench photo started me thinking. I really need one since I have a terrible time reading the markings on some chips. And I came up with an answer. Photograph it and zoom in w/ photo editing software.

screenshot.jpg
 

Yaakov

Joined Jan 27, 2019
1,612
An enhancement to that idea. Click on the second attachment to see the effect.

The laser etching used on many SMD parts can be very hard to read. For those that refuse to give up their secrets even under varied lighting and magnification, I have a trick that usually works quite well. All you need is a regular fluorescent highlighter pen and a UV light.

View attachment 171549

Run the highlighter over the part, as if highlighting something on a page. Then, wipe off the surface with a dry wiper or swab.

The ink retained in the etching will fluoresce more than what remains on the surface, revealing the part number in (relatively) easy to read illuminated lettering. If you desire it, some isopropanol can clean off the ink, but it's probably not required.

View attachment 171550

This has helped me in the past, I hope it can help someone else.
 

bertus

Joined Apr 5, 2008
20,226
Hello,

I also think it is the NE555.
Do you have a flatbed scanner?
I made a scan of two chip I had laying around:

Chips.jpeg

Can you read those?

Bertus
 

bertus

Joined Apr 5, 2008
20,226
Hello,

Can you see the production dates?
In that time there was no laser marking, but printed markings.
One chip has a plastic case, the other a ceramic case.

Bertus
 

Thread Starter

SamR

Joined Mar 19, 2019
1,614
Hello,

I also think it is the NE555.
Do you have a flatbed scanner?
I made a scan of two chip I had laying around:

View attachment 173043

Can you read those?

Bertus
It is the 555 and almost impossible to read even with my gooseneck LED magnifier. I've wiped them, wetted them, used the gooseneck plus another magnifying glass to increase the magnification, turned them all directions trying to get a good light angle on the markings and this beats them hands down for me using what I already have.

Yep, most printers have scanners now. Another good idea, but those chips look well marked compared to the ones I have trouble with. I'll try that next time I have trouble and thanks for the tip.
 

Wolframore

Joined Jan 21, 2019
1,518
I recently got a couple MPU9250 and 6050 gyroscope chips... the markings were so tiny I could not for the life of me read them... 4 lines of markings on a tiny QFN package... my son had to decipher for me.

This is what it looks like to me:
upload_2019-3-22_15-4-8.png
This is what's there:
upload_2019-3-22_15-2-41.png
 

Attachments

pmd34

Joined Feb 22, 2014
503
Hmmm yes, and thats while the packaging is still big enough for a couple of letters, many SMD components now just have a couple of meaningless letters or numbers, almost impossible to trace even if you can read them!
 

Alec_t

Joined Sep 17, 2013
10,690
For laser-etched markings, try smearing toothpaste or similar white goo over the surface. It fills the etch valleys and makes the marking distinct.
ChipMarks.PNG
 

Thread Starter

SamR

Joined Mar 19, 2019
1,614
I don't have the UV lamp (haven't used an EPROM eraser since forever), but am adding it to the Wishlist now.
 

Yaakov

Joined Jan 27, 2019
1,612
I don't have the UV lamp (haven't used an EPROM eraser since forever), but am adding it to the Wishlist now.
You can get a cheap UV flashlight, it is also useful for curing UV adhesives and resins. Only a few dollars for a totally functional one.
 

Thread Starter

SamR

Joined Mar 19, 2019
1,614
Yaakov said:
Run the highlighter over the part, as if highlighting something on a page. Then, wipe off the surface with a dry wiper or swab. The ink retained in the etching will fluoresce


I just tore down several breadboards that had impossible to read chips. Did this and it works much easier and quicker than my photo and zoom method. I ran a yellow highlighter over them and didn't wipe them before flourescing. Works perfectly. Kudos to Yaakov!
 

Yaakov

Joined Jan 27, 2019
1,612
Yaakov said:
Run the highlighter over the part, as if highlighting something on a page. Then, wipe off the surface with a dry wiper or swab. The ink retained in the etching will fluoresce


I just tore down several breadboards that had impossible to read chips. Did this and it works much easier and quicker than my photo and zoom method. I ran a yellow highlighter over them and didn't wipe them before flourescing. Works perfectly. Kudos to Yaakov!
Glad it proved effective. I struggle with markings sometimes.
 
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