LED power supplies in constant tension

The LED power supplies working with constant tension are used for LED called power LED which feed in constant continuous current. For it, it is necessary to use power supplies or drivers which guarantee an output in continuous constant current. These drivers play the role in the following way : Depending on the load detected in output varies the tension of output and it is stabilized in order that the current that crosses the circuit be nominal current in output (for exemple 350mA). In case a circuit is fed by several Led power, the connection of LED must be always IN SERIES.