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QFP bent leads

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#77171

QFP bent leads | 2 March, 2017

We have a board with an LQFP-176 with 0.5mm pitch. We regularly have to rework these due to unsoldered pins, which is due to pins that are slightly bent upward. We believe that we are receiving them this way, but it may also be due to handling on our part. Is this a common problem for parts of this size and pitch? I have yet to come up with any real solution short of recommending to the customer to redesign their board for the BGA version of this part.

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#77172

QFP bent leads | 2 March, 2017

Hi Rick,

we have seen this issue before with small volume and prototype parts coming in from catalogue suppliers, where they are decanted from the original manufacturers packaging and sold in smaller batches. Also after going out for programming.

Can you put a goods in flag on these and put them on 100% inspection for the next few batches? If so you will see where is issue is arising.

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#77175

QFP bent leads | 2 March, 2017

We usually receive them in batches of a few hundred, and occasionally from catalog vendors like Mouser. Inspection has been inconclusive. They don't have to be bent much to cause a problem. I'm wondering if it's just the nature of the beast.

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#77177

QFP bent leads | 2 March, 2017

Slim chance it's the nature of the beast if in original unopened package. If handled by anybody not properly trained they will get bent. Allso make sure your pick and place is seating them into the paste, any lead not contacting the wet paste will be open.

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Tom

#77185

QFP bent leads | 4 March, 2017

Could also be the leads catching on the feeder or tray during pick-up. I just had a feeder catching the edge of a lead as the part was picked causing the part to shift and be rejected at severe rates.

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#77280

QFP bent leads | 18 March, 2017

There are a few companies out there that manufacture lead forming/re-forming equipment. The equipment can effectively straighten the most bent-up leads. Fancort Industries is one of them, another is Hepco.

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#77387

QFP bent leads | 11 April, 2017

We have received partial trays from Mouser where they put foam over the tray taped tightly, but THIS IS NOT GOOG ENOUGH they must include TWO trays to keep the parts captive and safe. Just went through this with a customer supplied kit, and have started NCR with Mouser for some of our own purchased parts from them.

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