Where is pin one?

[depeje]

I was assembling a gadget I designed, but now I'm stuck at soldering an ST3232C. I can't seem to find which pin is pin one. Here's the datasheet: http://www.farnell.com/datasheets/2016317.pdf. Did they forget the dot, am I just blind?

[stmdude]

Check page 11 in the document you linked.

See how one of the edges of the chip is beveled ?  That's how you find pin 1.

[depeje]

Ok, so I am blind. I actually saw the line on the top view, but I was looking for it in laser etching.

Thanks!

[stmdude]

Ok, so I am blind.

So was I the first time I ran into it.

[brabus]

That has got to be the worst moulded package I have ever seen.

[m98]

Really, why couldn't they just add a normal pin mark on the laser etching? Wouldn't cost them a cent.

[TiN]

Running laser path cost time. In jellybean IC production even a second cost some money if you multiply it over millions of packages...
Beveled edge have pin 1, fairly usual thing.

[DTJ]

For DIL/DIP/SO parts where there is no pin 1 mark and the bevel or whatever is ambiguous I rely on the print orientation.

If the print is right way up then pin 1 is at the bottom left. Has anyone come across parts that break this rule? 


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[48X24X48X]

How usually I look for pin #1 follows the following sequence:

• Look for dot or line
• No dot, look for slanting edge
• No slanting edge, look at the direction of text

More and more IC are made without the dots these days.