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3D STEP Model Polarity Dot Missing on SOICs
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    Posted: 23 Sep 2025 at 1:00pm
1-i need more detail by what means "some 3D missed dot polarity"?
2-what are the packages have this note? 
3- how to correct this dot on 3D?
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Tom H View Drop Down
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Points: 5949 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 1:43pm
This package is not a Metric Pin Pitch SOP. The Package Marking has a Dot and no chamfer on the body. 

It is a 50 mil (1.27 mm) pin pitch SOIC. These packages were introduced in the early 1980's when the package had a 45 degree chamfer all along the Pin 1 edge. No Polarity Dot. 

You need to know the difference between Imperial and Metric pin pitch packages. 

We have no plans on changing this polarity marking concept that been around for the past 35 years. 

Metric Pin Pitch SOPs come in these Pin Pitches:
  • 1.00 mm
  • 0.80 mm
  • 0.65 mm
  • 0.50 mm
  • 0.40 mm
The Imperial Pin Pitch SOIC Packages come in these Pin Pitches:
  • 0.05" (1.27 mm)
  • 0.10" (2.54 mm)
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Points: 214 		Post Options Post Options   Thanks (0) Thanks(0)   Quote m.elsayed Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 4:02pm
Thanks Tom for your great support and help all time
just if can add more details for packages have this concept other than SOIC and SOP?
also is there any reference document i can read this point on it?
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Points: 214 		Post Options Post Options   Thanks (0) Thanks(0)   Quote m.elsayed Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 4:41pm
Thanks , Tom
but just if can add more details for packages have this concept other than SOIC and SOP?
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Points: 5949 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 4:46pm
If you see a small outline package with a Chamfer along the entire side of the body where pin 1 is, than you know it's a SOIC. 

If you see a small outline package with a Polarity Dot where pin 1 is, than you know it's a SOP. 

Metric Pin Pitch SOPs come in these Pin Pitches:
  • 1.00 mm
  • 0.80 mm
  • 0.65 mm
  • 0.50 mm
  • 0.40 mm
The Imperial Pin Pitch SOIC Packages come in these Pin Pitches:
  • 0.05" (1.27 mm)
  • 0.10" (2.54 mm)
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Points: 214 		Post Options Post Options   Thanks (0) Thanks(0)   Quote m.elsayed Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 4:50pm
Great Tom,

But I'm asking you to explain for the below packages which I think it have same case. 
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Points: 5949 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 5:30pm
The SOT component families are Small Outline Transistors. 

This is a TI SOIC. No Pin 1 Polarity Dot on the 3D Model. 


 
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Points: 214 		Post Options Post Options   Thanks (0) Thanks(0)   Quote m.elsayed Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 5:50pm
Can please have details for each package type in image like SOD, SODFL,SOFL,....SOJ, SOL,.... SOT223 (All package on mage)

What pitch should have dot and what pitch shouldn't have dot like what you explained for SOP package. 
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Points: 5949 		Post Options Post Options   Thanks (0) Thanks(0)   Quote Tom H Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 5:59pm
All SOT23s are metric pin pitch.
  • 0.95 mm
  • 0.65 mm
  • 0.50 mm
SOT223s come in various metric pin pitches and different pin quantities.

All SODs are 2-pin packages. No pin pitch.

All SOJs and SOLs are Imperial pin pitch and are on there way to becoming Obsolete.

All QFPs are metric pin pitch. 

SOICs are Imperial unit pin pitch and they are the only component family with a Chamfer on the Body along the top edge of where pin 1 is. 
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Points: 214 		Post Options Post Options   Thanks (0) Thanks(0)   Quote m.elsayed Quote  Post ReplyReply Direct Link To This Post Posted: 23 Sep 2025 at 6:33pm
1-what about other packages?
2-according to reply all Sot will have dot,so please why mentioned note may there is not?
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