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SN74HC4020: the chip pin oxidation.There is the phenomenon of pin oxidation, poor weldability

Part Number: SN74HC4020

Hi,

I bourght  some chips"sn74hc4020n"    250 pcs    from Mouser a few days before.(datecode of 17+  has  175pcs,  date of 18+  has  75pcs.) When my customer received the chips, They  found that the datecode of   18+ has the chip pin oxidation.There is the phenomenon of pin oxidation, poor weldability, see the attached picture, pin can not be tin.please see the attachment.

 My client is asking for a new shipment for them,but Mouser replied that they had no after-sales right. let me contact you.I really  need  your  help!Please reply  ASAP!Thank you very much!

  • Hello and welcome to the forums!

    The appearance of these pins is normal.  Please see this FAQ for details:

    Can you share the flux and type of solder being used for these devices? I would like to forward on to my quality/packaging department to see if they have any suggestions.

  • Hi,

    My customer  replied : TI's response only indicates that the surface of the pin may become rough as a result of the new process and appear to have been corroded, but does not result in a decrease in its weldability. Now we receive the pin weldability is poor, the picture is the phenomenon after welding, from the picture can be seen that its weldability is very bad.please  see  the picture .
    FLUX:Kester951
    SOLDER:ALPHA METALS VACULOY 6337
  • Thanks for the additional information.

    I will get back to you within the next 2 days.
  • I am working with my internal quality team to learn more about this issue. Can you tell me:

    (1) Is this the first time the customer has used roughened LF?

    (2) If not, is this the first time they’re seeing this issue on their roughened LF?
  • Hi,

    1)This is not the first time they've used it.

    2)But this is the first time they've had this quality problem.

  • Hi,

    How's the confirmation going?

    The client is urging me to reply.

    Please reply ASAP .

    Thank you!

  • All I have right now is confirmation that we will accept these devices as part of a Failure Analysis return. This will allow our lab to complete an analysis on the parts to determine what's going on.

    I haven't received any additional information.
  • After discussion with our internal experts, we have the following questions:

    Can we have the customer take a picture of the device mounted on the board?

    Could they specify which area they think is causing the problem?

    Our specialist doesn’t think the picture is clear enough to determine the problem from only that.
  • My client thinks the information they provided before is already telling.
    I'll try to communicate with them .
    But,will you be able to confirm what the problem is when you have the material you want?
    Or will it continue to be questioned?
    If possible,You can go to the client company and check it out.I think I'll get the answer faster.
    Because it's been going on for too long! I must give the client an answer as soon as possible.
    Thank you for your understanding!
  • We have a process for evaluating returned units.

    I hope that the customer has already started a Failure Analysis return through their distributor -- once TI receives the parts, we can start the analysis.

    There's no point in me guessing at the outcome of this analysis -- the whole point of us getting the parts back it to perform an analysis so we can figure out what is wrong.

    If I were to go to the customer, it wouldn't change the need for these parts to go to our lab and be tested.