The invention relates to a control circuit (3) for an electric motor, in particular for driving a windshield wiper, including a control means (16) comprising an output for controlling the electric motor, the control means being capable of varying the angle of the motor between a given minimum value and maximum value. In particular, the control means (16) comprises an input for receiving a speed set point and is capable of controlling the angular speed of the motor according to the speed set point, the control circuit likewise including a set point means (14) comprising an input for receiving values of the angle of the motor and an output for providing a speed set point to the control means, the set point means (14) being capable of determining the speed set point from a continuous function of the motor angle. The invention likewise relates to a driving mechanism (2) for producing an alternating rotary motion comprising a circuit (3) such as described previously and an electric drive motor (4), as well as to a windshield wiper device (I) including at least one driving mechanism (2) such as described previously and an windshield wiper arm (5) driven by the driving mechanism.