To enable single-supply operation, the device features an internal low-dropout regulator (LDO). The LDO is powered by the AVDD supply, and the 2.85-V (nominal) output is available on the DECAP pin. This LDO output powers the critical analog blocks within the device, and must not be used for any other external purposes.
Decouple the DECAP pin with the GND pin, as shown in Figure 41, by placing a 1-µF, X7R-grade, ceramic capacitor with a 6.3-V rating from DECAP to GND. There is no upper limit on the value of the decoupling capacitor; however, a larger decoupling capacitor results in higher power-up time for the device. See the Layout section for layout recommendations.