A good PCB layout for the TPA3130D2DAP involves keeping the input and output traces short and away from each other, using a solid ground plane, and placing decoupling capacitors close to the device. TI provides a recommended layout in the datasheet and application notes.
The gain setting depends on the input signal level and the desired output power. A higher gain setting can provide more output power, but may also increase noise and distortion. TI provides a gain setting calculator tool to help with this selection.
The maximum power dissipation of the TPA3130D2DAP is dependent on the ambient temperature and the thermal resistance of the PCB. TI provides a thermal derating curve in the datasheet to help estimate the maximum power dissipation.
The TPA3130D2DAP has built-in overvoltage protection, but it's still recommended to add external protection circuitry, such as a voltage regulator and TVS diodes, to protect against overvoltage and undervoltage conditions.
The recommended input coupling capacitor value depends on the input signal frequency and impedance. A general rule of thumb is to use a capacitor with a value of 1-10uF, but TI recommends consulting the datasheet and application notes for specific guidance.
TPA3130D2DAP datasheet
by Texas Instruments
