![]() | Imagine to have a pcb like the one beside, where the pads must be connected like is showed by the ratnest lines. There are no possibilities to turn around the pad externally, because the pcb cannot be bigger than showed and is also not possible to move the pad because the component mounted over the pcb have the pads at the distance showed in the image. The pcb only have one single layer, then, teorically, we can only directly wire the two central pads. |
![]() | When it's not possible to completly unroute a single side pcb
using only copper tracks placed into the layer Bottom Copper,
the only solution is to use jumpers placed over the component layer.
To create a jumper place two pads, with ![]() ![]() |
![]() | When you create a jumper, the jumper pads are electrically wired togheter
only if you use signal track line. The signal track
cannot be placed over the same layer of the track that we want to cross.
In this case, in fact, we'll have a short circuit! It is not correct to make a
jumper using a silk jumper line, because so there are no electrically
connection between jumper pads.
In fact, using |
When in a circuit there are some jumpers, sometimes, using
over a track, or
on the entire
circuit, Circad yellow hilights a specific pad, with the message
"Signal is linked to unknown pins" over the status line.
This happens because the components pads, and also all the pads automatically placed by Circad,
have a name, showed into the netlist and that you can see with
over a pad, but the manually placed pads
don't have an initial name ("Pin name"), if you don't set it first.
So, every time you'll obtain a message like the above, you'll must assign at all the
"anonymous" pads connected by the same signal line the name of the track, like
GND, +VCC or $000003. To known the track name you must use
over one of tracks pads.
![]() | Now, try to make a jumper in the TUTOR1.PCB pcb file, over the track that
connect the CONN1 pin 3 at the Q1 emitter pin.
Now, with ![]() ![]() ![]() |
![]() | Using ![]() ![]() ![]() | ![]() |