Abstract: An actuating device for a disc brake may have a piston, and a first ramp-ball motion converter having a first ramp portion axially constrained and actuatable in rotation around and actuating axis. The device may also have a second ramp portion coupled to the piston and a plurality of rolling elements interposed in contact between ramp tracks formed by the first and second ramp portion. The device may also have a second screw and nut motion converter connected between the second ramp portion and the piston. The device may also have a torque limiter that implements a torsional connection of the first ramp portion with the second ramp portion. The torque limiter may also decouple the rotation of the first ramp portion with respect to the second ramp portion about the actuating axis when a predetermined limit torque is exceeded.