yolco
Member level 2
Hi,
there are some doubts I need to solve before adding vias to the layout.
And finally, to sum up the steps to be able to add vias to design are:
Kind regards!
there are some doubts I need to solve before adding vias to the layout.
- Two types of vias are needed, through hole and BBvias, could the drill hole be the same for both of them?
- Via Pad <= 0.3 mm
- Via Drill Hole <= 0.15 mm
- Which would be the recommended pad & drill hole for different kind of via?
- Through Hole Via.
- Is it needed to have available pad in every inner layer?
- How can the pad be avoided into inner layers when it is only necessary to connect Top with Bottom layer? (Using "Suppress unconnected int. pads; legacy artwork" option from PAD Designer).
- Through Hole & BB via.
- At padstack definition, is it needed to define every layer on the future board (ex. 4 layers [Begin, L2, L3, Default Internal, End])? Or is it fine with simple definition (Begin, Default, End) and the later definition with BBvias setup and/or Constraint Manager?
- B(lind)B(uried) via.
- Which are the requirements for placing one via over another? (Stagger distance, number of layers at via definition).
- Once, set the contraint manager parameters, is something else you have to do for adding several vias to join several layers?
- Thermpad QFN ICs.
- At a QFN IC, a thermpad is present, then vias have to be added. At Pad Designer, this thermpad includes the drill hole parameters, and a multiple drill with the number of vias and their respective clearance (X,Y). How can these vias be defined to fit board requirements.
- I suppose this thermpad need to be added on constraint manager too. Is this right?
And finally, to sum up the steps to be able to add vias to design are:
- Create the via pad on Pad Designer.
- Make definition for similar vias from BB Vias Setup on PCB Editor. Setting start & end layers.
- Add via to physical contraint set, at respective top layer.
- At routing time, select start (Active) & End (Alternate) layers.
Kind regards!