A device includes a first line at the supply voltage; a second line at the boost voltage; a booster stage; a supply detecting stage connected to the first line and generating a first level signal when the supply voltage exceeds a first predetermined level; a boost detecting stage connected to the second line and generating a second level signal when the boost voltage exceeds a second predetermined level; a regulating stage enabled by the boost detecting stage; and a pump control stage, which generates a regulating enabling signal for the regulating stage in the absence of the first level signal and in the presence of an enabling signal enabling the boost condition. The regulating stage generates a regulating signal in the presence of the second level signal and the regulating enabling signal, when the boost voltage exceeds a third predetermined level; and the pump control stage generates a pump activating signal for the booster stage in the absence of the first level signal and the regulating signal.