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SN74LVC1G125: SN74LVC1G125 lead plating question

Christopher Rowe
Prodigy 10 points

Part Number: SN74LVC1G125

Tool/software:

Hello,

I am looking to know if Texas Instruments trims the leads post plating. We are seeing non-wetting to the end of the lead. The parts pre-solder suggest heavily this is what is occurring (see image below) but I need a confirmation that Texas Instruments does indeed do this so I can properly confirm it is so for acceptability in IPC-A-610 to prevent rework to correct.

This is in reference specifically to SN74LVC1G17DRLR leads but if this is a general practice, it would be great to know for future referees on parts.

Thank you,

-Christopher Rowe

Quality Engineer - Creation Technologies Rochester

  • 0
    TI__Expert 6960 points

    Hi Christopher Rowe,

    Yes, trimming the leads post plating is common for TI devices.

    Regards,

    Nikki

  • 0 in reply to Nikki Dengel
    Prodigy 10 points

    Hello Nikki,

    Is there a possibility that I can get this response formally in a letter or pdf of some sort? I ask because the customer I am asking the question for does not accept forum responses as official documentation when addressing the issue, which I brought up to customer support, and they suggested this course of action. Sorry for any inconvenience.

    Regards,

    -Christopher Rowe

    Quality Engineer - Creation Technologies Rochester

  • 0 in reply to Christopher Rowe
    TI__Expert 6960 points

    Hi Christopher,

    Let me look into it. Give me a couple days, and I'll get back to you.

    Regards,

    Nikki

  • 0 in reply to Christopher Rowe
    TI__Expert 6960 points

    Hi Christopher,

    Below is a link to a document about the DRL packages at TI (SN74LVC1G17DRLR and others) with regard to IPC standards. If this is not sufficient, please let me know.

    Lead Side Mold Flash of DRL Package

    Regards,

    Nikki

  • 0 in reply to Nikki Dengel
    TI__Expert 6960 points

    Hi Christopher,

    I see that this document does not resolve your problem. Could you be specific about what you need that is not listed in Lead Side Mold Flash of DRL Package?

    Regards,

    Nikki

  • 0 in reply to Nikki Dengel
    Prodigy 10 points

    Hello Nikki,

    The document was not sufficient. The document is for lead side mold flash. What we are seeing is non-wetting on the toe fillet due to the lead being trimmed which removed the solderable surface on part SN74LVC1G17DRLR. The document provided does not relate to this issue.

    The issue we are seeing is a defect per IPC-A-610 8.3.9 because the flat lug lead isn't meeting the minimum fillet height for a class 3. The reason I'm asking if this is per Texas Instruments design is because, if it is, then it is acceptable per IPC-A-610 8.3 as parts with surfaces that are not wettable by design are exempt from the criteria.

    We would like to know if this is by design, as we have not only had this issue on the SN74LVC1G17DRLR, but other Texas Instruments parts in the SN74LVC1G125 series as well as others. We can obviously tell it was cut but there's no documentation to support Texas Instruments doing so. So, I am trying to get the documentation so we know how to address this issue going forward and can back up that the lead was trimmed by design.

    Regards,

    -Christopher Rowe

    Quality Engineer - Creation Technologies Rochester.

  • 0 in reply to Christopher Rowe
    TI__Expert 6960 points

    Hi Christopher,

    My mistake for the misunderstanding. I'm in contact with the appropriate parties to help you get some documentation about this.

    Regards,

    Nikki

  • 0 in reply to Nikki Dengel
    TI__Expert 6960 points

    Hi again Christopher,

    I'm working to track down some information for you. Although trimming leads post-plating is common practice, it's come to my attention that this may not be the case for this specific device. Could you provide a lot code or image of the top marking of this device so that we can investigate further?

    Regards,

    Nikki