Pulse width controlled DC-DC converter having pulse width period control for influencing power consumption

A device for DC input power conversion from one or more solar cells, the device comprising:

• a DC-DC converter to be coupled to a DC source and provided with an inductor;
• and
• a power controller coupled to the DC-DC converter and provided with a pulse width modulator for controlling inductor current in a first mode during an adjustable part of a pulse width period having a fixed duration to charge one or more batteries;
• the power controller including a microprocessor and means implemented therein to adjust, during a second mode, an extended pulse width period during which power consumption of the controller is reduced, wherein
• the extended pulse width period is longer than the pulse width period of the first mode, and
• the controller is switched from the first mode to the second mode upon determination that an open terminal voltage of the one or more solar cells falls below 80% of a predetermined open terminal voltage.