Pin 1 Notch/Dot Not Visible on M24128-BFDW6TP EEPROM TSSOP-8 Package

ananda95msa · ‎2025-07-14

Hello ST Community ,

I am currently using the EEPROM part M24128-BFDW6TP (TSSOP-8 package) in a design. However, I’m facing difficulty in locating the Pin 1 marking on the IC. There is no visible notch or dot on the top side of the package that would typically indicate Pin 1, as referenced in the datasheet.

The IC top surface only contains part marking text, but no discernible Pin 1 indicator (notch or laser dot).
We’ve verified this across multiple units.
This is making it difficult to confidently orient the IC for placement.

I’ve attached a clear screenshot for your reference.

Could you please confirm:

The official Pin 1 location with respect to the printed text on the IC?
Whether this is a known marking issue or within tolerance of ST's marking process?
Any additional guidance or recommendations for identification?

Thanks and Best regards,
Ananda

mƎALLEm · ‎2025-07-14

Hello,

Normally, this is the pin 1:

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TDK · ‎2025-07-14

Pin 1 is on the chamfered side of the chip.

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mƎALLEm · ‎2025-07-14

Hello,

Normally, this is the pin 1:

To give better visibility on the answered topics, please click on "Accept as Solution" on the reply which solved your issue or answered your question.