Control device for an electrical load, said device comprising: - an input connector, having a first input electrical conductor and a second input electrical conductor for connection thereof to a DC electrical power source, - an output connector, having a first output electrical conductor and a second output electrical conductor for connection thereof to an electrical load to be controlled, - a main switching electronic component that is electrically connected to the first input electrical conductor by first input connecting means, and that is electrically connected to the first output electrical conductor by first output connecting means, in order to be in series with the electrical load to be controlled, - a flyback diode that is connected so as to be reverse biased in parallel with the electrical load to be controlled, in order to allow the current generated by an inductive component of the electrical load to flow when the main switching electronic component is turned off, - a switch controller able to generate a substantially square-wave width-modulated control signal that drives the switching of the main switching electronic component alternatively between an on state and an off state; - the main switching electronic component is an SMC; - the main switching electronic component comprises a body that is thermally coupled to one of the input or output electrical conductors (4a, 4b) or (5a, 5b) respectively) by conduction through respective first or second input or output connecting means (10a, 10b or 11a, 11b respectively); characterized in that: - the body of the main switching electronic component is mounted on a first electrically insulating substrate, - the first electrically insulating substrate is structured so as to have a thermal conductivity higher than 0.8 W/m.°K, and preferably higher than or equal to 5 W/m.°K, - the first electrically insulating substrate is thermally coupled by conduction to another of the input or output electrical conductors (4a, 4b or 5a, 5b respectively), so that the heat generated in the main switching electronic component during the operation thereof is evacuated to at least two input or output electrical conductors (4a, 4b or 5a, 5b respectively) that are separate from one another. - an input connector, having a first input electrical conductor and a second input electrical conductor for connection thereof to a DC electrical power source, - an output connector, having a first output electrical conductor and a second output electrical conductor for connection thereof to an electrical load to be controlled, - a main switching electronic component that is electrically connected to the first input electrical conductor by first input connecting means, and that is electrically connected to the first output electrical conductor by first output connecting means, in order to be in series with the electrical load to be controlled, - a flyback diode that is connected so as to be reverse biased in parallel with the electrical load to be controlled, in order to allow the current generated by an inductive component of the electrical load to flow when the main switching electronic component is turned off, - a switch controller able to generate a substantially square-wave width-modulated control signal that drives the switching of the main switching electronic component alternatively between an on state and an off state; - the main switching electronic component is an SMC; - the main switching electronic component comprises a body that is thermally coupled to one of the input or output electrical conductors (4a, 4b) or (5a, 5b) respectively) by conduction through respective first or second input or output connecting means (10a, 10b or 11a, 11b respectively); - the body of the main switching electronic component is mounted on a first electrically insulating substrate, - the first electrically insulating substrate is structured so as to have a thermal conductivity higher than 0.8 W/m.°K, and preferably higher than or equal to 5 W/m.°K, - the first electrically insulating substrate is thermally coupled by conduction to another of the input or output electrical conductors (4a, 4b or 5a, 5b respectively),