For best overall performance, place all circuit components on the same side of the circuit board and as near as practical to the respective LDO pin connections. Place ground return connections to the input and output capacitor, and to the LDO ground pin as close as possible to each other, connected by a wide, component-side, copper surface. The use of vias and long traces to the input and output capacitors is strongly discouraged and negatively affects system performance. The grounding and layout scheme shown in Figure 11-1 minimizes inductive parasitics, and thereby reduces load-current transients, minimizes noise, and increases circuit stability.

Using a ground reference plane either embedded in the PCB itself or located on the bottom side of the PCB opposite the components is beneficial to the layout. This reference plane serves to assure accuracy of the output voltage, shield noise, and behaves similarly to a thermal plane to spread (or sink) heat from the LDO device when connected to the thermal pad. In most applications, this ground plane is necessary to meet thermal requirements.