Single-cell Power Supply

A good way to minimise energy losses in a charger is to use a switching regulator, and if we use a regulator with a step-up topology then we can simultaneously reduce the number of cells needed to power the circuit. Fortunately it is not too difficult to design a step-up converter suitable for use in portable equipment as the semiconductor manufacturers make a wide range of devices aimed at exactly this kind of application. The Maxim MAX1708 is one example.