A device for regulating the supply to a photovoltaic converter, the device comprising: a laser source (2); a photovoltaic converter (6) that feeds a DC-DC converter (8); circuit (100) for regulating the input impedance of said DC-DC converter (8) as a function of the operating voltage (Us) of the photovoltaic converter (6) and of its no-load voltage (Us0); and circuit (42) for measuring an output voltage of the DC-DC converter (8) and for producing a regulation signal (SR) for regulating the laser source.