Non-linear, 3D cyclic dynamo in global turbulent simulations of Strugarek et al. (2017). The rising/sinking convective cells are shown by the dark/bright patches in the convective envelope. A quadrant of the sphere has been cut out (white lines) to reveal the self-consistent generation of strong toroidal magnetic field (red-white ribbon) at the base of the simulated convection zone. A potential extrapolation of the magnetic field outside the star is shown with red/blue tubes labelling magnetic field lines exiting/entering the solar surface.