The present invention relates mainly to a brake booster that is adjustable, notably in terms of the value of the jump. Advantageously, according to the invention, the target value for equilibrium of operation of the booster actuator is altered. A target value of a signal delivered by a position sensor is defined either by programming the electronic control unit or by selecting a coefficient in a program as a function of the braking characteristic or characteristics that it is desired to implement. Once the setpoint value has been determined, the electronic control unit commands the actuator using a setpoint value so that the actuator permanently and dynamically works toward achieving the previously defined and/or selected target value. The setpoint may be calculated as a function of torque, force, position or some other parameter.