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Steve.Picotest , 03-24-2020, 09:19 AM

Does anyone have a footprint for X2SON5 package (SOT1226) for 74LVC1G08DPWR (TI) or 74LVC1G08GX (Nexperia)? I can't find it anywhere and have been unable to create it myself. This s a 0.85mm package and is the larges package that will fit on my PCB. Any help is greatly appreciated

robertferanec , 03-25-2020, 09:43 AM

You may be able to use standard rectangular / square pads, maybe rotate them and just adjust solder mask. I would probably do it that way - I try do not use special shaped custom pads as they can make problems when board is imported / exported between different softwares.

Steve.Picotest , 03-25-2020, 09:59 AM

Thanks! I'll try that

Ivan , 04-06-2020, 07:30 PM

Hello Robert

I agree but in some cases better to use recommended footprint otherwise you can face issues at manufacturing.
Actually I had the same question "how to create such parts in altium?" - part number is LP5907SNX-3.3/NOPB from TI...



... but finally I created it using copper polygons and put on top small pads.
I am not sure how to do it in Altium correctly but in Mentor PADS I was associating these copper islands to their pads.

Thanks for your answer.

robertferanec , 04-08-2020, 08:06 AM

I have tried to use polygons in footprints in past, but I have not found the right way to do it (in PCB it was always causing problems - didn't pick up net names correctly and there was DRC). But I was probably doing something wrong. @Ivan does it work for you in PCB without DRC?

PS: Still I try to avoid it. I import and export between different CADs a lot and often these unusually shaped pads cause problems and need to be manually fixed.

Ivan , 04-08-2020, 03:01 PM

To be honest I see a bunch of errors and the way Altium is representing them a bit confusing. To me Altium is a new design tool and I am still at the beginning of the process.

In this light I have two questions:
1. Is there a good video I can watch how to understand errors in design?
2. I can share the file with you (I created it in training purposes) and you can have a look at it.


Export between tools causes manual fixing all the time, more or less, no matter which footprints you use.

Ivan , 04-09-2020, 05:23 AM

Actually I figured out how DRC works. Basically is very fancy and I would say it is discouraging. It controls so many fabrication features which I've never checked before. For example, silkscreen to soldermask, solder mask sliver, and so on..good or bad - I would say it is very confusing because fab houses don't provide so many details regarding their process, I guess, until you request it.
I searched a bit in Google and found this. https://www.eurocircuits.com/altium-...-design-rules/

They give templates to design PCB conform to eurocircuit capabilities but not sure whether they can be used, will see.

Again, not sure how to use it properly, may be I need to switch off a bunch of features and leave only known ones.

To the subject about complex footprint - Altium is not complaning, no ERC are found.

robertferanec , 04-10-2020, 06:09 AM

PCB Manufacturer can manufacture almost everything - so even without specific rules they still may be able to manufacture your PCBs. The thing is, if you follow some rules, you can save a lot of money and troubles - that is where all these rules will get handy. For example, if you use 0.3mm track width/space then your PCB is going to be much cheaper as if you use 0.075mm track width/hole. Also, if you set correct rules, the board you design will be exactly the board you will receive (e.g. if you leave very thin solder mask sliver between pads, then you may think it will be there, but PCB manufacturer may remove it because they will not be able to manufacture it).

So you would like to be sure, that on your PCB there are no these special places which could increase your PCB price or make it hard to manufacture.

This may help:
- How to design cheaper PCB? What the parameters on PCB manufacturer website mean? https://www.youtube.com/watch?v=NyVjg6-wfvY
- EEVblog #1259 - PCB Manufacturing Options EXPLAINED: https://youtu.be/mT2Vp3HcIP4

1) The best is to understand first how PCB is manufactured. The videos above can help with that.
2) The best place to ask questions is here on this forum