Good power-supply decoupling is important to achieve optimum performance. AVDD, AVSS (when using a bipolar supply), and IOVDD must be decoupled with at least a 1-µF capacitor, as shown in Figure 107, Figure 108, and Figure 109. A 270-nF capacitor is required on the VNCP pin when using the negative charge pump. Place the bypass capacitors as close to the power-supply pins of the device as possible with low-impedance connections. Using multi-layer ceramic chip capacitors (MLCCs) that offer low equivalent series resistance (ESR) and inductance (ESL) characteristics are recommended for power-supply decoupling purposes. For very sensitive systems, or for systems in harsh noise environments, avoiding the use of vias for connecting the capacitors to the device pins can offer superior noise immunity. The use of multiple vias in parallel lowers the overall inductance and is beneficial for connections to ground planes. The analog and digital ground are recommended to be connected together as close to the device as possible.