Switching class, watt-level power generation at wide-area IOT and ISM frequency bands with mixed-signal approaches offer great promise for time-division duplex protocols. While DAC-like in architecture, the so-called Digital Power Amplifier requires special attention to radio frequency artifacts for higher order modulation EVM and ACLR. Fully-depleted FDSOI offers new, low-power methods for implementing power calibration and AM-to-PM path phase alignment. These techniques are developed and explored from system behavioral through transistor level simulations.