Chapter 16. Power Systems
Designers are sometimes confused about how to deal with multiple power planes on printed circuit boards and how to deal with their separation. We often talk about the horizontal separation between planes as a split, and there are some design rules that may apply when designing in the area of splits.
Before we talk about how to deal with splits between planes, it is instructive to talk about why we have separate power planes in the first place—to accommodate separate power supplies. One reason we might have separate power supplies is because we might have different voltages in our circuits. The issue of separate voltages might thus be a reasonable place to start.
Power Supply Voltages
On any given board, or in any given application, ...