The PCM514x family of devices are simple to layout. Most engineers use a shared common ground for an entire device. GND can consider AGND and DGND connected.
Good system partitioning should keep digital clock and interface traces away from the analog outputs for highest analog performance. This reduces any high-speed clock return currents influencing the analog outputs.
Power supply and charge pump decoupling capacitors should be placed as close as possible to the device.
The top layer should be used for routing signals, whilst the bottom layer can be used for GND.
11.2 Layout Example
It is recommended to place a top layer ground pour for shielding around the DAC and connect to lower main PCB ground plane by multiple vias