Ground and Vcc plates in board layout not found?

Layout
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Hi there,

I have completed laying out my devices on my board and have drawn tracks connecting each component and am now in the step of creating a ground plate on the bottom layer and a Vcc plate on the top layer.

When I go to “Place” a zone, I am not given an option in my “Net” drop down for GND and VCC. Are these something I import in a library? If so, where can i find them?

I am following along with the tutorials on youtube.

Also, I am looking to finalize my board before sending to the manufacturers. What are some key final checks I should be making?

Thanks in advance!

-Wissam

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Because you have drawn tracks, I assume you have a corresponding schematic from which you have pushed the footprints and nets to the board.

A design doesn’t have GND and VCC nets automatically, you have to add them to the schematic, possibly using power symbols.

2 Likes
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Yes, you’re right. Where can I find power symbols?

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image

You don’t need to use them. You can just attach a label to the net wire.

1 Like
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Thank you kindly! I loaded a power library into my schematic and updated my PCB with the new schematic. The GND and VCC nets are now showing…

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GND and Vcc planes should not be an afterthought for the last few minutes of a design.
If you have dedicated power planes on a 4 layer board, then you probably know what you’re doing and just getting familar with KiCad.

If you’re just beginning with PCB design as a hobby project my advise is to post your (zipped) design here and I’ll have a look at it and try to give some advise.

1 Like
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As a new user, it will not let me upload files. Do you have an email?

Thanks,
Wissam

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You are now a “basic” user. Upload away. :wink:

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PCB_DESIGN.zip (79.2 KB)

Thanks for the help! I’ve attached my files :slight_smile: I hope I am not missing too many things in my design. I followed along with the tutorial videos.

Thanks again,
Wissam

10

So this is clearly a beginners project.
Probably the first ever PCB design you made.

Some good things:
I can open and view the schematic and PCB.
When I run a DRC check on the PCB, it even reports no errors, which shows me that you also probably also did the DRC check during the design process.
“There is plenty room for improvement” :slight_smile:

Now the “bad” things:
An electronics schematic is much more then a means to generate a netlist to make a PCB from. Those are not even the most important goals of the schematic.
The first and very important goal of a schematic is to make it human readable. This is so you (and others) can understand what is the meaning, and how it is supposed to work.
For example, It was only after searching on the 'net for the MAX756 that I found out it was a voltage regulator chip.

Another (obvious to me) thing that is missing, is a connector to put power into your board (This is normally a schematic symbol, just like IC’s and passive components).

The circuit for the LM35 is also not going to work. AVcc of the Atmega328 is a power input and should always be connected to the Vcc pin of the Atmega328.
There are also no decoupling capacitors on the board.
I also see 2 big caps: C2 which is 150uF and C3 which is 100uF.
Capacitors of these sizes are usually electrolitycs, but you use schematic symbols for non polarised capacitors. C3 is also a very small SMD capacitor on the PCB. That is never going to work.

There are also many other issues, and the amount of effort I am willing to put into this is limited. About a year ago I did this for another beginner. My advise to you is to read that thread and implement the advise given there:

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