For LDO power supplies, especially high-voltage and large output current supplies, layout is an important step. If layout is not carefully designed, the regulator can fail to deliver enough output current because of thermal limitation. To improve the thermal performance of the device, and to maximize the current output at high ambient temperature, spread the copper under the thermal pad as far as possible and place enough thermal vias on the copper under the thermal pad. Figure 8-3 shows an example layout.