I just heard someone say that we should not use vias for power lines in designing a PCB. Why is that? And is it absolutely necessary, as I am currently designing a PCB and it's not possible to follow this rule on my board to 100 percent.

 

I just heard someone say that we should not use vias for power lines in designing a PCB.

And did this "someone" say why?

 

And did this "someone" say why?

nope..

 

I would think the main concern is the amount of current going through the via.
If it's more than few hundred mA or so then you may want to use more than one via in parallel to minimize the resistance.

 

DEpending on the board production process, some vias do not have enough current carrying ability for some applications.And also, all vias add a bit of inductance to the trace. On may instances it is possible to put several vias very close for the same trace, which is one option. If the board uses through-hole parts, a via at a lead hole may be a cheap fix. I have done that and it worked for me.

 

I usually fill the via hole by soldering a wire (tinned copper) through 'pin' on both sides same gauge as the via hole.
Also specify a larger dia via.
Max.

 

The vast majority of modern complex circuit boards are made with multiple layers with power and "ground" on inner layers. You cannot use such a board without vias to the power layers. On a double sided board, it is generally impossible to distribute power without the use of vias.

Where current level or the requirement for inductance is critical, it is common to use two or more closely spaced vias in parallel.

Power distribution on a PCB needs to be a priority in the layout. Adequate decoupling capacitors that are properly placed are necessary.

 

How much current is the via expected to conduct?