A multi-purpose battery charging circuit being selectively configurable in a charge-and-play mode (opt1, opt2) for operating a load circuit separated from a battery and simultaneously charging said battery from a power supply or in a simple charge mode for charging a battery connected to the load circuit, said multi-purpose battery charging circuit comprising: - a first node to which the power supply is connected; - a switch for coupling the load circuit to the battery via a second node in the charge-and-play mode (opt1, opt2), - a third node to which said battery is connected; said first node being coupled to the second node via a fourth node, and - a voltage regulator means, coupled between the first node and the second node, a first switching means, coupled between the first node and the fourth node; a first multiplexing means, for selecting a driver means (300, 350, 320) for driving said first switching means amongst at least a first (300, opt1), a second (350, opt2) and a third driver means (320,opt3), said selected driver means (300, 350, 320) controlling said first switching means, the first driver means being arranged to protect the load circuit from an overvoltage, the second driver means being arranged to maintain the second node at a slightly higher voltage than a voltage at the battery, and the third driver means being arranged to regulate the voltage during charging with no load circuit; and a second multiplexing means, for selecting said second driver means if said first multiplexing means selects said second driver means, said second driver means controlling a second switching means connected to said fourth node, and for deactivating said second driver means from the second switching means if said first multiplexing means selects said first driver means or said third driver means; - an external energy storage means if said first multiplexing means selects said second driver means, or a short-circuit means if said first multiplexing means selects said first driver means or said third driver means, said external energy storage means or said short-circuit means being connected between said fourth node and said second node; - a bi-directional switching means coupled between the second node and said third node, controlled by a fourth driver means for allowing a current flowing from said second node towards said third node to be reverted in order to flow from said third node towards said second node, wherein said driver means is arranged to allow said current flowing from said second node towards third node to be increased during charging; - said voltage regulator comprising at least said first switching means, said second switching means and said second driver means. - a first node to which the power supply is connected; - a switch for coupling the load circuit to the battery via a second node in the charge-and-play mode (opt1, opt2), - a third node to which said battery is connected; said first node being coupled to the second node via a fourth node, and - a voltage regulator means, coupled between the first node and the second node, a first switching means, coupled between the first node and the fourth node; - an external energy storage means if said first multiplexing means selects said second driver means, or a short-circuit means if said first multiplexing means selects said first driver means or said third driver means, said external energy storage means or said short-circuit means being connected between said fourth node and said second node; - a bi-directional switching means coupled between the second node and said third node, controlled by a fourth driver means for allowing a current flowing from said second node towards said third node to be reverted in order to flow from said third node towards said second node, wherein said driver means is arranged to allow said current flowing from said second node towards third node to be increased during charging; - said voltage regulator comprising at least said first switching means, said second switching means and said second driver means.