Author Topic: pin 1 location  (Read 767 times)

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Offline Hornnumb2Topic starter

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pin 1 location
« on: May 27, 2022, 02:59:24 pm »
trying to figure out which is pin one on this eeprom. Thanks
 

Offline tooki

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Re: pin 1 location
« Reply #1 on: May 27, 2022, 03:13:52 pm »
Unless there’s a clear marking to indicate otherwise, with the text oriented normally, pin 1 of an IC is always bottom left.

And of course there’s always the datasheet. You can find those online.
 

Offline gamalot

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Re: pin 1 location
« Reply #2 on: May 27, 2022, 03:14:44 pm »
Bottom left corner in your image. Although this package does not have a dot to identify the Pin 1, it should have a chamfer on the lower bottom side.

https://www.st.com/resource/en/datasheet/m24c16-w.pdf
« Last Edit: May 27, 2022, 03:19:47 pm by gamalot »
 

Offline jmelson

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Re: pin 1 location
« Reply #3 on: May 27, 2022, 03:16:47 pm »
The chamfered side of the chip appears to be toward the bottom of the picture.  If so, pin 1 is at the bottom left.
Jon
 

Offline m k

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Re: pin 1 location
« Reply #4 on: May 27, 2022, 06:02:36 pm »
Is there a round leg of something at the bottom right of the picture?
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Offline mikeselectricstuff

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Re: pin 1 location
« Reply #5 on: May 27, 2022, 06:07:58 pm »
bottom-left, indicated by chamfer
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Offline MikeK

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Re: pin 1 location
« Reply #6 on: May 27, 2022, 11:24:24 pm »
Also, the chamfer should be indicated in the datasheet.
 

Offline DavidAlfa

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Re: pin 1 location
« Reply #7 on: May 28, 2022, 02:31:46 pm »
Sometimes there's also a mark under the IC.
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Offline VK3DRB

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Re: pin 1 location
« Reply #8 on: May 30, 2022, 12:35:17 am »
If there is no top overlay ("white ink"), one might ask why there is no pin one marker on the PCB. Saving cents perhaps?

If there was a pin 1 marker, the best PCB pin 1 markers are solid filled triangles, not circles that look like fly vomit or vias. Triangles are superior for a number of reasons. But most engineers use the default fly vomit because they don't know much better or don't care.
 


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