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The Chosen One , 03-28-2025, 02:29 PM

Anyone here really good/knowlegeable about RF design? This is my first RF design and I am looking for any and all helpful feedback for it

QDrives , 03-28-2025, 04:15 PM

Let me start with a whole series of style comments and some functional ones too.
In the screenshot below:
1) Do not write "u1" for a 0.1uF capacitor as it is confusing with component "U1" (if you have any). Better use "100n" instead.
2) Do not have lines through text.
3) Why do your resistor and capacitors have the pin numbering visible?

QDrives , 03-28-2025, 04:19 PM

4) Using "Netlabel x" as a netlabel is not helpful. Use functional names.
5) Have the line under the netlabel.
6) If a pin is not used / connected, do not draw schematic lines to them. You will notice that if you run ERC it will flag the pin as not connected.
7) Did you notice that the resistors here do not have pin numbers?

QDrives , 03-28-2025, 04:24 PM

8) The CC1 pin has a connection dot and a ERC exemption. Why?
9) In schematic you should set the grid to 100mil. It prevents these small jumps in position. Also make sure that all symbols have the pins on 100mil grid.
10) 100p decoupling on Vbus? Does not help much. Better make that 100n. Also missing is the inductor / ferrite bead.

QDrives , 03-28-2025, 04:30 PM

11) Here the texts and symbols are overlapping so much that you cannot read the designator nor the value.
12) Notice the different capacitor symbols? 3x 100nF? Why not the 1uF you also have in the design? Or is it because you have 3 pins and they are not next to each other?
13) I am missing pin numbers in the IC.
14) Where does power net "PPS" come from? It is a normal net from the IC, not a power net.

QDrives , 03-28-2025, 04:32 PM

15) Why 2 LDOs in parallel?

QDrives , 03-28-2025, 04:35 PM

16) Why are you using USB-C connectors for CAN?

QDrives , 03-28-2025, 04:36 PM

17) As for layout --> https://www.youtube.com/watch?v=F6iBKXAfC5Q

The Chosen One , 03-31-2025, 12:17 PM

I was concerned about current draw, that’s why I put two in parallel

The Chosen One , 03-31-2025, 12:18 PM

This was something we wanted to switch to and do can via usb-c. Before we were just using male headers with jumper wires. Is there a better way to connect can networks?

QDrives , 03-31-2025, 02:52 PM

The problem is not current draw with an LDO, but power. Power is (Vin - Vout) * Iout.
From 5V to 3V is 2V drop. USB-C does a max something like 2A, so you can dissipate 4W.
Have plenty of heatsinking capability (package and copper area).

QDrives , 03-31-2025, 02:56 PM

Check CiA 106, (https://www.founderchip.com/zb_users/upload/2024/05/20240506202011171499801144104.pdf)