Voltages generated from a battery decrease over time. If a system needs a stable voltage and it is powered by a battery, a DC/DC converter can stabilize the voltage source. Regulated DC/DC converters can accept a wide input voltage range and convert it into a regulated and stable voltage. A good example of this would be a 12 V battery that usually has a voltage range from 14 V down to 9 V. By adding a +12 V DC/DC converter, the design assures that the load will always see a constant 12 V.