@paulvdh oh yes I have this problem really couldn’t draw a rectangular
I didnt know about aligning I will read the manual
Thanks 
By the way I am involving on downloading Kicad 5 if I succeed I will edit my PCB and upload for u. but I want to comment that this board will get input in 2 ways : 1- connecting directly to another board TX RX
2- connecting through RS232
if the first one is selected the level shifter will be assembled(ADM325 will not be assembled)
if the second one is selected the ADM325 will be assembled(and level shifter will not be assembled)
and for the interface it can be with RS485 or CAN communication
I ve not sent it to the manufacture yet. The reason of small vias was that because some tracks were just 0.3mm and I thoughut its better to use smaller vias for these kind of traces
Not all vias need to have the same hole diameter. Plated through holes are created by plating and if you cut down the center of the via you will see the copper midway through the via is noticeably thinner than near the surface of the board. By bumping up the via hole size you are creating a much better conduction path.
– Small soapbox:
I learned abut PCB’s as an engineer. Where the success of a product was often effected by the board layout and design. I learned the hard way that defaulting to the minimums is just a lazy way of designing a board an often added problems we didn’t need.
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Where is VDD5v_ISO coming from?
I see no input connector for that power supply voltage.
I do not know if I’ve said it before, but why so many Isolation barriers?
I can understand in having a barrier between the STM32 and the Uart (probably to a PC), but there do not seem to be any other off-board connections.
For the secondary side of the RS-232 you can “steal” some power from RS232, and for the “remote” STM32 board you can put CAN, RS485 & Power through a single cable. If you do this, then the remote board does not need a power supply.
How long are the cables?
For long cables it’s best to use a high voltage over the cables (24V or higher), and then use a local SMPS circuit to make 5V or 3V3.
Alternatively you can add small isolated DC-DC converters.
The board with the power supply would get a 5Vdc to 5Vdc converter for the isolated part, and a 5Vdc to 24Vdc converter for the cable, and on the other board you can use the 24V(Maybe saged to 21V because of cable resistance) to generate the local power supply voltages.
These DC-DC converters are made by lots of companies.
https://duckduckgo.com/?q=2W+DC-DC+converter+isolated&iar=images&iax=images&ia=images
For long cables both CAN and RS485 need twisted pair. CAT-5 cable works pretty good.
CAN needs the same sort of termination resistors as RS485.
R18 has the same function as R22. It is not 120R/0R for R18, but 120R or open.
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VDD5v_iso coming from a 9db connector on the right bottom
@paulvdh thanks so for your helping and useful comments
Actually I had some problems on downloading version 5 kicad but fortunatelly finally I ve succeded to install kicad 5 I will edit it soon and upload it again
Sorry here where I am the time is 1am 
I will answer to your question tomorrow
Thanks thanks for spending time on my first design
Oops.
I saw the label, but did not realise the BAT1000 was a diode in a SOT-23 package.
Don’t rush. I’ll guess you will need a few days to digest it all.
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Hi @paulvdh I have learned a lot from your comments
Thanks a lot
And thanks all great members spending time to help others
Unfortunately I couldnt follow all comments for my pcb as I was in hurry but be sure I will follow and obey your comments for my next pcb
Thanks again 
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