Switching Power Supplies A - Z

Chapter 6

noise, and all its attendant problems. The smaller the switch transition time, the more are the

possible consequences, as we see.

The first requirement for the designer is to understand the flow of power-related currents in

the converter. This leads to an identification of the troublesome or “critical” traces of the

PCB; we must pay the closest attention to these traces. We will also see that this

identification process is very “topology-dependent.” So we can’t, for example, design the

PCB for a buck-boost, the same way we would do it for a buck. The rules change

significantly! We may thus also realize that very few PCB layout persons out there ...