11.1 Layout Guidelines
No PCB layout is perfect, and compromises are always necessary. However, the basic principles listed below (in order of importance) go a long way to achieving the full performance of the TPS65133 device.
- Route discontinuous switching currents on the top layer using short, wide traces. Avoid routing these signals through vias, which have relatively high parasitic inductance and resistance.
- Place C1 as close as possible to pin 12.
- Place C2 as close as possible to pin 3. Place C3 as close as possible to pin 9.
- Use the exposed thermal pad to connect GND, AGND and PGND.
- Use a copper pour (preferably on layer 2) as a thermal spreader and connect it to the exposed thermal pad using a number of thermal vias.
Figure 28 illustrates how a PCB layout following the above principles may be realized in practice.