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OPA2171: Pinouts for SOT-8 "D" package for OPA2171

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Part Number: OPA2171

Just to clarify, there is no indication on the OPA2171 datasheet (or Google Images) for that matter that tells where Pin 1 is.

This is an SOT-8 "D" Package surface mount component.

There is no dot on the physical chip, only a Line which I assumed indicated Pin 1, but I am no longer in the business of assuming anything, we even called TI and couldnt get a straight answer to such a basic question.

so here is a link I found that confirms.

https://www.evilmadscientist.com/2010/basics-finding-pin-1/

"There’s a printed bar on the left hand side of this chip to act as a polarity indicator, taking the place of the half-moon shape."

  • Hi Alex,

    Yes. The stripe at the top is the Pin 1 marking.

    The convention for most plastic rectangular packages is:

    looking at the package in a horizontal direction (pins facing up and down), reading the text correctly from left to right, pin 1 is in the lower left. The pins are numbered counter-clockwise across the bottom and around to the top (so bottom is 1-8 left to right, and top row is 9-16 right to left).

    Also notice that there is a bevel in the package along the length of the pin 1 edge. This is also common on SOT-23 packages.

    So there are several clues as to the pin one position:

    1. Dot or bump next to pin 1
    2. Notch, bar or stripe at the pin-1 end of the package
    3. Bevel along the pin 1 edge of the package
    3. The text orientation
    4. Notch in "foot" or a wider pin 1 (rare)
    5. Beveled pin-1 corner (rare)
    6. Angled edge on any thermal pad under the package

    Dots and bars are preferred because of optical inspection and placement.

    Regards,

    Paul Grohe

    TI Comparators (CMPS) Applications Group

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