SLAU472C February 2013 – November 2023 TAS2505 , TAS2505-Q1
If a single 1.8V rail is used for the AVDD supply and the DVDD supply, generating the 1.8V from a higher battery voltage via a DC-DC converter results in good system-level efficiency. The 1.8V rail connected to the DVDD pin can also be connected to the AVDD pin. The device operates with this connection, but the achievable performance is a function of the voltage ripple typically found on DCDC converter outputs. To achieve specified performance, an external low-input-voltage 1.6V LDO must be connected between the 1.8V rail and the AVDD input. During operation, the LDO is deactivated via the LDO_SEL pin to connect the SPKVSS pin.