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The datasheet of old LM78H12K chip

Hello,

I am looking for the datasheet of the old chip labelled as LM78H12K. It was originally manufactured by the National Semiconductor company, which is now a part of Texas Instruments. Is there any archive of these old datasheets? I would really appreciate that.

Photo of the chip:

Thank you very much!

  • Hello Vojtech,

    While I research this request, as the LM78H12K seems to be an obsolete device, there is an E2E post that at least shows the pinout and package: https://e2e.ti.com/support/power_management/linear_regulators/f/321/p/545084/1990043 .

    And just curious, are you using this for a new design, or redesigning a product?  If so, perhaps we can recommend a newer, enhanced performance device?   I'll just need the requirements for the design.

    At your service,

    ~Leonard  

  • also, just FYI, the basic LM7812 datasheet is here: http://www.ti.com/lit/ds/symlink/lm7800.pdf , although the 'H' and 'K' designations do not appear in this version.

    ~Leonard 

  • Here's the first rev of the datasheet from 2000.

    The specific variation you asked about is not highlighted.  I'm wondering where you got the picture, and if your design actually uses these?

    ~Leonard 

    LM78xx[snosbr7a].pdf

  • In reply to LeonardEllis:

    Hello, thank you very much for the datasheet. Still I am not sure this is the right one, this doesn't contain "H" and "K" designations - I believed that "H" stands for 5A output and "K" means TO-3 package. (There are old datasheets such as uA78H05 from Fairchild or 78H12A from New Era Electronics which contain the letter "H".)

    I got that chip from e-bay reseller (the photo is from that store), so this chip may be a fake and who knows what is inside...

    Attachments:
    78H12A-New-Era-Electronics.pdf
    uA78H05-Fairchild.pdf

  • In reply to Vojtech Husek:

    Vojtech,

      I have not been able to come up with any additional documentation for this device.  Since it is an obsolete device, not orderable, I'm wondering if you would be  interested in a newer device that will meet your design needs?  If your design requires 12V at 5A, we can certainly come up with an alternative.  What is the VIN, and what is the product you are designing?  Would you be willing to review and use a newer device? 

    ~Leonard 

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