Hello,

This is a crazy issue. Apparently, Molex changed the orientation of a part but did not change the part number. The orientation changed so much that if the part is auto placed by a machine the orientation of the signal pin and ground pin gets swapped, meaning the signal pin goes to ground on the connector, and the ground pin goes to the signal pin of the PC board. It's the craziest thing I've ever seen I think when it comes to part ID's. (see attachment)

The ramifications are intense and very serious. If two parts, with completely different pin orientations are purchased, how do you know how to place the parts on the PC board. You would have to have a human operator examine each part in turn closely so they can figure out how to solder it to the board.

This is the first time I ever saw this from what I can remember. It is especially concerning in the modern age of automatic parts placement machinery.

Here is the part number:
Molex 73412-0110 UMCC Coaxial Connector

There are two drawings, one shows the notch in the upper right-hand corner of the part, the other shows the notch in the lower left-hand corner. That effectively reverses the little ground pin and the signal pin. I can produce the drawings if you would like to examine them. The attachment shows the two excerpts.

My only thought is to contact the company and find out what is going on. This can affect millions of PC boards out there, meaning many of them would have to be reworked by hand.

Any thoughts?

 

Have a look at Molex product change note PCN 511407.
Looks like the notch will in future indicate the ground connection not the signal and there are some other dimensional changes.

 

That is unacceptable.
If a part is changed in any manner, then there's no excuse for it not to have a new part number.

 

Not exactly the same, but we found this with a spray kitchen cleaner. Exactly the same labeling, description and part number, but the formulation changed, changing to a less-effective grease cutting agent and adding an ingredient to which my partner has a high sensitivity, causing contact dermatitis.

 

I agree that It’s difficult to see how the changes made by Molex on this connector are in accordance with the normal rules for form fit and function.
Always tempting to choose a revision rather than the mountain of paperwork generated when changing part numbers!

 

Have a look at Molex product change note PCN 511407.
Looks like the notch will in future indicate the ground connection not the signal and there are some other dimensional changes.

Hi,

That's interesting, where did you find that note?

 

Not exactly the same, but we found this with a spray kitchen cleaner. Exactly the same labeling, description and part number, but the formulation changed, changing to a less-effective grease cutting agent and adding an ingredient to which my partner has a high sensitivity, causing contact dermatitis.

Hi,

I have seen these kinds of changes before but never with an electronic part in such a way that it voids the correct operation when used in the same way as the 'older' part.

I've also seen food changes too. One time I was surprised when I found a pack of noodles felt too light when I got home and picked it up preparing to cook them. I checked the package stamped weight; it was 4.5 ounces. That was same as before, but I could tell it was different. Put it on the scale, 3 ounces. They reduced the quantity inside but never changed the package weight. That can't be lawful. Sometime later, they did change the package to 3 ounces. The other catch was the price never changed, it never went down, only the amount of the contents of the package went down.

Another big surprise came when i found out that Pyrex glass used for making those graduated glass measuring cups changed from borosilicate glass to some sort of tempered glass which is less expensive.

There are so many changes I have seen over the years, and they are almost always snuck into the product without much warning. I didn't think a company like Molex would do this kind of thing though.

 

Molex has an excellent documentation system.
Just go to their website and search for the part number.
You will find drawings in most formats together with change notes, 3d models etc.
As I messaged previously, I think that it should have had a different part number for the sake of traceability but what you should do is speak with a Molex representative and get the full story.

 

Molex has an excellent documentation system.
Just go to their website and search for the part number.
You will find drawings in most formats together with change notes, 3d models etc.
As I messaged previously, I think that it should have had a different part number for the sake of traceability but what you should do is speak with a Molex representative and get the full story.

Hi,

Yes I agree. The key point I think is that the part changed with no part number change, and how do they notify the entire community about something as silly dilly as that.
I might write to them about this just to see what their excuses will sound like.

Maybe they don't like to use the word "obsolete". They would have to make the old part obsolete if they changed the part number and didn't feel like making any more of the old style.

If I find out more I'll post here, or if anyone else feels like asking them about this please report back here too. Thanks.

 

For auto placement this change will not cause an issue as the device is oriented with the signal pad towards the carrier sprocket holes in both versions of the carrier tape.
The issue arises when dealing with the connectors when removed from the tape such as in r & d and small batch prototyping.
It also has a legacy issue if pcb designs include the notch in silk screen.

 

For auto placement this change will not cause an issue as the device is oriented with the signal pad towards the carrier sprocket holes in both versions of the carrier tape.
The issue arises when dealing with the connectors when removed from the tape such as in r & d and small batch prototyping.
It also has a legacy issue if pcb designs include the notch in silk screen.

Hi,

Oh that's interesting, I have not investigated that part yet. Thanks.