Disclosed examples include isolated dual active bridge (DAB) DC to DC converters with first and second bridge circuits, a transformer with a sense coil, and a secondary side control circuit to provide secondary side switching control signals to regulate an output voltage or current signal by controlling a phase shift angle between switching transitions of the secondary side switching control signals and switching transitions of a secondary side clock signal, where the secondary side control circuit includes a clock recovery circuit to synchronize the secondary side clock signal to transitions in a sense coil voltage signal of the sense coil.