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SMT Component placed upside down

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Hi all, Having a major problem with an IC being placed up... - Jul 27, 2005 by crishan  

#35774

SMT Component placed upside down | 27 July, 2005

Hi all,

Having a major problem with an IC being placed upside down. We pick up the fault at AOI.

We have check several reels and the component is not placed upside down by the supplier. Where should I start looking; 1. Are we using an incorrect feeder 2. pick up nozzle 3. Incorrect placement depth / kiss off pressure incorrect

The IC is an OP amp AD8541 AKS 5V R & R Package size: SC70-5R (5 PINs, 3 on one side and 2 on the other)

Thanks Crishan

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aj

#35776

SMT Component placed upside down | 28 July, 2005

Are you seeing many of the components in the reject bin of the machine? If it is feeder related I would expect to see some rejects unless the part is jumping and landing in the same orientation i.e. 3 leads on same side everytime!

Other than that I would say that the part has to be upside down in the reel or else someone is playing games with you!

Have someone inspect every board after the placement machine and other stations pre AOI, this will help pinpoint the problem.

aj

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#35780

SMT Component placed upside down | 28 July, 2005

Check the pick postion in the feeder. If the nozzle is picking at the edge of the component, it could flip it. BTW what kind of machine are you using?

Stephen Olan

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bobpan

#35781

SMT Component placed upside down | 28 July, 2005

When we see the upside down part problem its typically feeder related....either the feeder is making the part jump or the z is taught tooooooo deep causing the part to jump before its in its pick location.

chow

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#35783

SMT Component placed upside down | 28 July, 2005

Hi,

Your not using vibration feeder here are you? I have seen this a lot with vibration stick feeders.

Regards,

Grant

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#35784

SMT Component placed upside down | 28 July, 2005

Most likely a feeder that has a rough advance. This can cause the part to flip in the tape before the nozzle gets it.

Jerry

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SuMoTe

#35790

SMT Component placed upside down | 28 July, 2005

I'm thinking vibe feeder as well. I saw this alot on older machines (Quad IVC) vibe was set too high making parts jump around. If it is a vibe feeded, look for spillage behind the feeder base.

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Jason Fullerton

#35810

SMT Component placed upside down | 29 July, 2005

Definitely feeder related - we get it all the time on those package parts. If you can, slow the tact of the feeder advance a bit (if it's on T&R). We also don't catch it at placement, but at pre-reflow visual or AOI.

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Stefan

#35831

SMT Component placed upside down | 1 August, 2005

If you are using vib. feeders than the component may be flipped length wise by the following components. Components should be landing with the leads on the right side but upside down. If you are using tape feeders the component may be flipped sideways. Another problem source could be the cover tape and static charge. If your tape feeder peels off the cover tape within the pick up window, than the component could be inverted by the cover tape.

You can hardly flip a component with too much air kiss. However, you can possibly lift and drop a component with no air kiss.

reply »

crishan

#35832

SMT Component placed upside down | 1 August, 2005

Hi All,

We are not using a Vib. bowl feeder, or stick feeder, these parts are on a reel.

The pick & place machine we are using is a Panasonic brand YV100X, its a single head with 8 nozzles.

What we are finding is that the component package size is too big, so that at the pick up position the component can be on the edge of the nozzle, which we believe is causing it to flip.

I am not sure if there are anyway to centralised the component at pick up position.

Cheers

Crishan

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aj

#35838

SMT Component placed upside down | 2 August, 2005

Crishan,

You must be seeing an incredible amount of Attrition on this component if this is the case.

You should most definitely be able to put in a Pick-up offset either at the machine or in the part data.

aj

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Stefan

#35843

SMT Component placed upside down | 2 August, 2005

Tape feeders usually have a fixed pick position regardless of the package size. Is the component body off center in the tape pocket? I hope you can enter an offset in the feeder set up file. Also, perforation holes can deform, if the reel is too heavy, causing the component to stop before pick position. Components can pass pick position if the cover tape is pulled too much.

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GS

#35844

SMT Component placed upside down | 2 August, 2005

Are the pick up nozzles metal made (ironmagnetic material)? Some time magnetic residual on metal nozzles can generate pbm like that when chips terminations have nickel and when SOt or similar packages have terminal A42 alloy made.

Time ago got pbm like that with 0603 Resistors and SOT23 (skewing)placed by Pnasert MV-100 (nozzles metal), pbm solved by periodical nozzle demagnetization.

GS

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#35849

SMT Component placed upside down | 2 August, 2005

Thanks for the comments everyone. I did not think of checking the nozzles material, I will check this out.

GS, What is PBM, is this some sort of ironiser.

Also to clarify, we believe the that the pocket size for the component is too big allowing the component to freely move around, so at pick up we are not quite sure the exact position of the component in relation to the pocket.

So even with an pick up offset, it might work for some, but might not for others.

Since the supplier is not willing to reduce the package size, I am trying to see if there is another way we can confidently : 1. reduce the part movement within the reel pocket 2. somehow still pickup the part accurately with the variation.

Cheers

Crishan

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CG

#35853

SMT Component placed upside down | 3 August, 2005

Regarding the issue of using a pick-up offset: I really can't see any benefit to this if the pockets in the tape are too large, since this means that you cannot be sure that the components always end up in the same position when the feeder indexes.

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GS

#35871

SMT Component placed upside down | 3 August, 2005

Hi Crishan, sorry, "pbm" is a short way to say problem.

In the past ('89), we had same magnetic pbm also with metal nozlles on Dynaper MPS-2500.

Some time, we found also chips received from supllier already magnetized. Solution was to put the reel on de-magnetizer machine for few minutes intil no more magnetic residual was on chips metalization. Magics ? no, only experience of headache pain solved.

Regards

GS

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rcarlos28

#35902

SMT Component placed upside down | 3 August, 2005

Crishan, Do you check the Nozzle orientation? some machine use a Rectangular o circle nozzle body, and this reduce the vaccum. When this component is taked from the feeder and the camara measured recognized the pins? Do you change the type of recognition.

this is adittional of the pick up of the feeder. some feeders need a low calibration in time sincronize to the time of the machine. Mechanical feeder has a nut o bolt excentric and Electronic Feeder needs electronic pulses to control the motor forward.

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lloyd

#35917

SMT Component placed upside down | 4 August, 2005

I'm not overly familiar with the Pana machines but I recently had the same issue with a SOT23. We have an option on our machines to switch on an early vacuum on pickup and it was this that was causing the problem. I'm not overly sure how it caused this problem, whether air turbulence in the pocket turn it or the vacuum sucked it out of the pocket an onto the nozzle upside down, but when I switched this off the problem went away! If you have a similar option on your machine it wouldn't do any harm switching it off.

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#36108

SMT Component placed upside down | 12 August, 2005

Is it possible to advance the feeder at shorter intervals? So every time the part is picked the feeder moves 2 times shorter movements instead of one long move? Just a thought.

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Reflow Oven

Essemtec Fox Compact Automatic Pick and Place