I’m learning both electronics and PCB making, I’ve been up to this all day now, I’ve set up an incoming 12v+ with a schottky diode and a capacitor and want to pass this power on to a microcontroller. The thing that puzzles me is why “ratsnest” suggests to bind 12v directly from incoming JST pin when I place it physically closer to the VIN pin in the PCB Editor. I mean, I’m asking because i’m probably doing a mistake somewhere and I dont want that to follow me down the path of my carrier.
If I move it away from that position the line from 12v pin goes away and is routed via the diode and capacitor.
I have tried changing nets, labeling nets, adding netclasses.
This is normal behavior. The main purpose for a schematic is to be human readable. If a human can’t read / verify the schematic, then making a PCB is only GIGO.
On a schematic things are drawn in a logical order by function, while on the PCB, the way currents run though the parts is important. There is no relation to the “connection order” on the schematic and on the PCB. The ratsnest is just a reminder that some connections in a net still have to be routed, and the ratsnest is just shown between the closest pins of a net.
In addition, watch out for those green wires over pins of symbols and the small open squares. They are unconnected wire ends, and are often an indication that KiCad does not recognize a connection.
The ratsnest needs to be taken in its entirety - it’s just showing you how all those pins need to be connected electrically, but doesn’t take how you’ve laid out the schematic in to account.
The ratsnest display algorithm will show the nearest connection between items, but this doesn’t mean that connecting them in another way is wrong - that’s up to your layout decisions.
Good catch! That wire is not attached to the +ve side of the capacitor. Check out ERC checks to help you catch unconnected pins! (From the Inspect->Electrical Rules Checker menu item).
Almost good, and that is why I added often in my previous post. If you look at the ratsnest lines, you see that both terminals of C1 are part of the netlist.
In this particular case the attachment point of the pin is actually in the junction dot. If the pin was not connected you would see a round circle at the attachment point of the pin.
Another small tip: PCB Editor / Preferences / Preferences / PCB Editor / Editing Options / Ratsnest [x] Show ratsnest with curved lines makes the ratsnest clearer on a crowded PCB. Increasing it’s line thickness is sometimes also beneficial.
The rest seems to have been solved, but I question your power connections (bottom left in your schematic).
First, attaching a power symbol to a connector in that way is… exotic.
Second, is -12 V really the same as GND? You need to make up your mind (it could be correct, but is unusual).
One tip for clear readable schematics: voltages drop from top to bottom, so your +12V symbols should point up and be above the ground symbols. Second: signal flow is from left to right. So inputs are pointing to the left and outputs to the right. These are no fixed rules and not the best choice in every case, but you see it very often and it helps to grab the essenced of a design in a moment.
Besides that, if you use the diode as reverse current protection you should put a fuse or a resistor between the input and the diode, otherwise it is possible that the diode breaks as open and you still have the reverse voltage across you circuit and (probably) everything else still goes up in flames.
Also I’d rotate C1 and D1 so that they’re vertical next to each other (with the GND connections pointing down of course). Makes it clearer that they’re for smoothing and clamping the voltage.
Thanks to both of you.
