ATTiny4313 DIP legs breaking off

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My apologies if this has been discussed before. About 6 months ago, production switched from using a 20 pin DIP ATTiny2313 to a 20 pin DIP ATTiny4313. 

There have been some reports of the legs breaking off much easier on the new ATTiny4313’s. After grinding off the top of the IC, there are rectangular cutouts in the legs. Is this normal? Why are the cutouts there? (See the red arrow in the attached image) 

To me, the cutouts weaken the legs.

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Last Edited: Fri. Sep 5, 2014 - 10:59 PM
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I would guess that the idea is for the epoxy to hold the leadframe more securely.

Looking at pin#20, the 'locating hole' is not going to weaken the leadframe metal very much.

Mind you, how often would you remove a DIP20 chip from a pcb or DIL socket ?

After all, God gave you ICSP programming!

David.

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I assume they were breaking off when being re-inserted into a socket, and that they weren't soldered into a PCB and breaking in a high vibration environment?

+1 on David's comments. Lots of Threads about small area connectors for ISP that don't take up much PCB area.

Was the chip the only change? Perhaps a new socket, perhaps a new gorilla working the bench who isn't as gentle as they should be?

Also, are we discussing the first time insertion of new chips into the PCB socket, or repeated insertions?

For manual first time chip insertions I often find it necessary to pre-bend the pins in a bit to make insertion doable. I bend an entire row simultaneously by pressing them against the table.

JC

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I remember seeing a pin straightening tool for sale, some years ago. They are still available:

http://www.google.com/webhp?nord...

One of them should minimise stress on the pins.

Leon Heller G1HSM

Last Edited: Fri. Sep 5, 2014 - 04:53 PM
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Like others I kind of wonder when this damage was occuring? In a production environment surely you only use DIP because you want to use a 1 sided PCB and wave solder it? You aren't seriously using DIP sockets in production are you? If you are, why are the chips being removed/replaced more than once? Or is this damage really happening during a single insertion?

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More details:
We use about 200-400 per day of the ‘4313. The part is machine inserted and this where the pins are being broken. Granted, we are not seeing a huge number of pins breaking off, but when we would have a mis-insertion previously, the pin would usually bend and not break off. The end product is a gasoline pricer 7-segment display. The PCB is double sided, in circuit programmed, and wave soldered with all through hole components. (including 100’s of 5mm LED’s on some boards) There is no socket on the PCB for the ‘4313. As most of you know, gorillas in production are very common. :)
Thanks for the comments so far.

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Quote:

Thanks for the comments so far.

Any tequila in the area?

Quote:
Play Music
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She said, "I'm going out with my girlfriends
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Drop a contact down the sink

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If the DJ puts Bon Jovi on
She might come home in a table cloth
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She can handle any champagne brunch
A bridal shower with Bacardi punch
Jello shooters full of Smirnoff
But tequila makes her clothes fall off

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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I'm going to assume, since you went to the trouble to torture the poor micro, that a close inspection of the PCB didn't reveal the hole to be inadvertently filled with solder from the tinning process. JC

 

Edit:

Oh man, perhaps this was the last post on the "Old Forum"

 

I had just finished it when the site went dead, and the timestamp is 3:01 PM, which was about shut down time.

 

JC

Last Edited: Sat. Sep 6, 2014 - 03:33 AM
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Jay, I think Michael has claimed that honour and JJ gets the first on the new site. Now... where did I read that...

Ross McKenzie ValuSoft Melbourne Australia

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Matt6ft9, Looking at your avatar, I think you should see a doctor

The largest known prime number: 282589933-1

It's easy to stop breaking the 10th commandment! Break the 8th instead.