Hello, I'm trying to start a project that include a pro micro below are my work so far with some modification. Will it work of something might fried up?
Please make your question more clear.
0.1uF caps on the crystal pins are definitely not good. They should be 22pF, something in that range. The signal will not oscillate with 0.1uF.
Do you want LED1 and LED2 to turn on? Connect the Cathode to GND instead of 5V, then turn them on with a high output.
If you want a low output to turn them on, then flip the LEDs so the Anode connects to 5V.
How did you select 5.1K for the CC1 & CC2 signals?
Big one: Will you need SCK/MOSI/MISO connected in order to install a bootloader into the chip, so that serial downloads will work thru the USB connection? Or will the bootloader be installed prior to the chip being installed on the board?
In addition to CrossRoads comments:
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RESET: Look at one of the Arduino schematics, you can put a capacitor to ground so the µP will reset on power on. BTW RESET is really RESET\ where the slash means (a logical) NOT. This means the chip is reset when the RESET\ pin is low.
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CRYSTAL: The physical layout of the crystal is critical. You should look as the Atmel datasheet and maybe app notes.
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Personally I would always put some sort of connection on every usable pin. Even if its just a test point dot. You never know when you might need to connect something to it. This unless your are very space limited.
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You have not reverse polarity protection. It is advised.
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I'm assuming this is a hobby board, perhaps your first. Its been my experience the first board usually has some issues. So try to make a layout that can be modified.
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It is easy to leave component off when you built your board. Its very difficult to add them where there is no space. So If you think you might need some component put it in.
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When you go to layout your board do not use the default trace width or via hole diameter. These are usually the MINIMUM the mfg can supply. Unless you design absolutely requires small size features, increase the default by a factor of ~2.
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Before you send your design out to be mfg, print out a 1:1 and lay your components on the printout. Your design is pretty simple as far as parts footprints go. Many errors have occurred by having relays, transformers etc upside down. Your only risk from what I see is the connector. DO NOT rely on the library footprints as your might be a slightly different version. It is important to verify the components will fit. This is also a good time to catch if you designed in a 0805 but need a 1206
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Don't forget to add mounting holes (if you plan to use them). Getting a board up and running just to not know how you plan to mount it is extra effort you likely don't need.
Good luck.
CrossRoads:
Please make your question more clear.0.1uF caps on the crystal pins are definitely not good. They should be 22pF, something in that range. The signal will not oscillate with 0.1uF.
Do you want LED1 and LED2 to turn on? Connect the Cathode to GND instead of 5V, then turn them on with a high output.
If you want a low output to turn them on, then flip the LEDs so the Anode connects to 5V.
How did you select 5.1K for the CC1 & CC2 signals?
Big one: Will you need SCK/MOSI/MISO connected in order to install a bootloader into the chip, so that serial downloads will work thru the USB connection? Or will the bootloader be installed prior to the chip being installed on the board?
Thank you for the feedback. Both of the caps and led has been fixed. For the bootloader, I had thought to put some probe point to burn it on. For the resistor on cc1 and cc2 I followed a guide on a kicad forum in order to make usb c function as a 2.0 connection which is kind of a pain since you would need to put probe point in order to burn the bootloader.
JohnRob:
In addition to CrossRoads comments:
RESET: Look at one of the Arduino schematics, you can put a capacitor to ground so the µP will reset on power on. BTW RESET is really RESET\ where the slash means (a logical) NOT. This means the chip is reset when the RESET\ pin is low.
CRYSTAL: The physical layout of the crystal is critical. You should look as the Atmel datasheet and maybe app notes.
Personally I would always put some sort of connection on every usable pin. Even if its just a test point dot. You never know when you might need to connect something to it. This unless your are very space limited.
You have not reverse polarity protection. It is advised.
I'm assuming this is a hobby board, perhaps your first. Its been my experience the first board usually has some issues. So try to make a layout that can be modified.
It is easy to leave component off when you built your board. Its very difficult to add them where there is no space. So If you think you might need some component put it in.
When you go to layout your board do not use the default trace width or via hole diameter. These are usually the MINIMUM the mfg can supply. Unless you design absolutely requires small size features, increase the default by a factor of ~2.
Before you send your design out to be mfg, print out a 1:1 and lay your components on the printout. Your design is pretty simple as far as parts footprints go. Many errors have occurred by having relays, transformers etc upside down. Your only risk from what I see is the connector. DO NOT rely on the library footprints as your might be a slightly different version. It is important to verify the components will fit. This is also a good time to catch if you designed in a 0805 but need a 1206
Don't forget to add mounting holes (if you plan to use them). Getting a board up and running just to not know how you plan to mount it is extra effort you likely don't need.
Good luck.
Thanks for the advice, will work on the reset and reverse polarity protection. For the mounting parts, space doesn't bother me for now since it is my first project. The problem that I faced is that most of the schematics online prefer caps and resistor on 0603 footprint which is quite small. Is it okay to switch to bigger one like 1206?
1206 is fine.
I always use 0805 if possible, 0603 is too small for me to handle (age?). Some resistors I use are only available in 1206 (1 watt usually).
Please do yourself a favour and add the 6pin ICSP connection. You will thank yourself.
Willem.
Edit: Fixed the sizes - thanks for the explanation.
That's 0805, 0603, imperial (not metric). It stands for 0.08x0.05 and 0.06x0.03 (inches)
I'd suggest when starting out to go no smaller than 0805 (imperial) - most component dealers will
show both imperial and metric sizes, just be sure you don't order the wrong size!
Invest in some ceramic-tipped tweezers too, really handy as they are non-magnetic and
handle high temperatures without issue. They are tougher than metal tweezers too, incredibly.
Thanks for the component size suggestion.
Willem43:
Please do yourself a favour and add the 6pin ICSP connection. You will thank yourself.
After spending some time searching it seems like it will be a lot easier to have on board. Your suggestion is really appreciated.
MarkT:
Invest in some ceramic-tipped tweezers too, really handy as they are non-magnetic and
handle high temperatures without issue. They are tougher than metal tweezers too, incredibly.
I will try to look for one since I have one but it is metal and almost short some electronic before.
The problem that I faced is that most of the schematics online prefer caps and resistor on 0603 footprint which is quite small. Is it okay to switch to bigger one like 1206?
As previously stated 1206 is functionally acceptable. But before you go below 0805 make sure the parts you want are available in 1206. As the industry goes, so goes the parts. Smaller and cheaper are the direction things are going.
BTW: making parts larger is never a problem as long as the voltage and power rating are equal or better than those called out in the instructions.
I don't know how much flexibility your CAD program has. Perhaps you can have a pad layout that would accept both 1206 and 0804.
Hi,
Hello, I'm trying to start a project that include a pro micro below are my work so far with some modification. Will it work of something might fried up?
Where is the Pro Micro in your circuit.
Why didn't you just put some headers in your PCB and plug in a ready made and ready to program Pro Micro?
What is the application?
Tom... 
TomGeorge:
Hi,
Where is the Pro Micro in your circuit.
Why didn't you just put some headers in your PCB and plug in a ready made and ready to program Pro Micro?What is the application?
Tom...
I'm integrating it directly onto the board itself. Currently trying to explore more, of course I could just plug it in a premade one but I'm trying to make my future projects a lot more clean. If it succeed I would like to use it to control some led or a switch matrix.
JohnRob:
As previously stated 1206 is functionally acceptable. But before you go below 0805 make sure the parts you want are available in 1206. As the industry goes, so goes the parts. Smaller and cheaper are the direction things are going.BTW: making parts larger is never a problem as long as the voltage and power rating are equal or better than those called out in the instructions.
I don't know how much flexibility your CAD program has. Perhaps you can have a pad layout that would accept both 1206 and 0804.
The footprint can be adjusted by layering both footprint. Another question is it okay to put ground copper region on top and bottom of the board? Some people just put it on one side either the top or bottom.
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