2017-07-14 03:48 PM
Our tech managed to mount a '407 180 degrees out. We figured out that it was because there is a molding mark 180 degrees from the pin 1 mark and they really aren't that different.
Why not use the pin 1 mark as the injection port? That way you can even save a feature on the mold.
Just a thought.
Andrei from The Great White North.
2017-07-14 05:57 PM
I think the pin one dimple and it's counterpoint are ejector points, so I doubt there's a savings to be made, but the clarity on pin one could certainly be improved. Not sure that's best done with the laser, or a different type of mark.
2017-07-16 07:42 AM
Dears,
The optional marking / ejector holes depends on our supply chain operations that may change as described below for LQFP144. as a general recommendation for LQFP packages : Pin 1 is on bottom left corner when you read the Product identification : STM32Fxxx.
Cheers,
STOne-32.
2017-07-16 10:05 AM
While the text is certainly a big cue, you definitely have parts where the pin 1 is less than crystal clear
Note also the round, some what indistinct round laser mark next to the ST Logo, these aren't helpful to the casual inspection
2017-07-16 10:28 AM
Ok, and here is the part that breaks the manual, and the one I looked at last night when responding to Andrei's question, the other F407-DISCO boards I looked at this morning lacked the ejector. As a casual observer you can see why this could be place 180 from desired.
So that's one packaged in the Philippines,
Here's one from Korea, which is orders of magnitude clearer
Apologies for all the different image orientations/angles, doing this with my cell phone, trying to get the lighting to capture the surface details, and stay in focus.
2017-07-16 10:31 PM
That's unpossible Clive, here is the '407 LQFP100 manual package description.
There's no mention of the ejector pin details that you show in your pictures. (troll lol lol lol oooo)
STOne-32, yes, this seems to be an issue.
Andrei from The Great White North (grey today, from the forest fire smoke)
2017-07-17 02:44 AM
Andrei,
On the current STM32F407 Data Sheet DocID022152 Rev 8 09-Sep-2016 it says above that diagram, 'The following figure gives an example of topside marking and pin 1 position identifier location. Other optional marking or inset/upset marks, which depend on supply chain operations, are not indicated below.'
On this maybe, give them a break?
2017-07-17 10:52 AM
I don't think any of this is meant with meanness or anger, it's just frustrating. The manual really should have a comprehensive set of examples covering the assorted supply chain and encapsulation variations, it can be a separate document for all I care. I can provide my people on the line and in the lab with an array of photos to help identify pin one, but there's no guarantee its current or has 100% coverage. I've got other 407 from China here also, and don't think I've got pictures of all the other variants to hand.
My frustration would be the counter-pointed ones, where the ejector mark is opposite and of similar depth, radius and profile, and result in 180 placement. The manual picture with two ejection points counter to each other and not opposite pin 1 perhaps less so.
2017-07-17 11:05 AM
Addendum : Having a disclaimer that basically translates to 'parts might not look like this at all' seriously devalues the document and it's fitness for purpose.
2017-07-17 03:09 PM
Dear all,
As said earlier , we provide only examples of packages in our product datasheets, However we are following standard of industry, Our MCUs in LQFP packages are shipped and supplied in tape and reel media compliant with
with EIA 481 and IEC 60286-3 standard specifications.
You can refer to this Technical Note
applicable to all STM8/STM32 Products, then Section 4 - Device Orientation.Cheers,
STOne-32.
For @ Andrei : I missed yesterday New GOT Season 7, It was at 3:00 Central Europe Time ;)