Electronic circuit for an energy supply device, especially for a charging device for batteries

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the control terminal (14), in particular the gate terminal, of the switching element (10) is additionally connected to a terminal (17), in particular a collector terminal, of another switching element (18), in particular a transistor.

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the through connection, in particular a collector-emitter connection, of the other switching element (18), in particular the transistor, is disposed between the control terminal (14), in particular the gate terminal, of the first switching element (10), and the preferably negative potential.

Electronic circuit as claimed in one or more of the preceding claims, characterised in that a terminal (12), in particular the drain terminal, of the first switching element (10) is connected to the output terminal (7, 8) and preferably via a resistor (20) to a control terminal (21), in particular a base terminal, of the second switching element (18).

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the control terminal (21), in particular the base terminal, is connected to a control device (11) of the power supply device (1).

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the control terminal (14), in particular the gate terminal, of the first switching element (10) and/or a terminal (17), in particular a collector terminal, of the second switching element (18) is connected to the control device (11).

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the first switching element (10) is activated when the power supply device (1) is switched on, even if no consumer (9) is connected.

Electronic circuit as claimed in one or more of the preceding claims, characterised in that the switching element (10) is activated at a specific polarity when a consumer (9), in particular the accumulator (3) is connected to the output terminals (7, 8) , even if no power source (6) is connected to the input terminals (4, 5).

Method as claimed in one or more of the preceding claims, characterised in that for the purpose of the overload protection system, when the polarity of the consumer (9) is at the specific (correct) polarity and too high a current flow is passing across the first switching element (10), the latter is deactivated by the second switching element (18).

Method as claimed in one or more of the preceding claims, characterised in that in order to operate the overload protection, the first switching element (10) is periodically switched on and off until the current flow being established across the first switching element (10) falls below a defined value and the voltage appearing at a control terminal (21) of the other switching element (18) also falls below a pre-defined value, preventing the other switching element (18) from being activated.

Method as claimed in one or more of the preceding claims, characterised in that when the first switching element (10) is deactivated on expiry of a pre-settable time by a control device (11) of the power supply device (1), the other activated switching element (18) is deactivated and the first switching element (10) is automatically re-activated by the applied voltage.

Method as claimed in one or more of the preceding claims, characterised in that for the purpose of the load detection system, the control device (11) firstly deactivates the first switching element (10) by activating the second switching element (18) and on expiry of a pre-settable time, activation of the second switching element (18) is terminated, and if a consumer (9) is connected, a voltage is applied to the control terminal (21) of the second switching element (18), as a result of which the first switching element (10) remains deactivated due to the self-holding function and this is detected by the control device (11).

Method as claimed in one or more of the preceding claims, characterised in that for the purpose of the load detection system, in particular for detecting the accumulator (3), whilst the first switching element (10) is deactivated, the output voltage at the output terminals (7, 8) is increased by the power supply device (1) by a specific amount, in particular 1V to 5V, and the control device (11) terminates activation of the second switching element (18) so that if a consumer (9), in particular an accumulator (3) is connected, a voltage appears at the control input (22) of the second switching element (18) and the second switching element (18) therefore remains active on the basis of the self-holding function, and this is detected by the control device (11).

Method as claimed in one or more of the preceding claims, characterised in that the control device (11) detects that the first switching element (10) has been deactivated due to the fact that a control input (22) of the switching device (11) is coupled with a control terminal (21) of the first switching element (10) and, as a result, when the second switching element (18) is activated, the voltage appearing at the control terminal (21 ) of the first switching element (10) is applied to the preferably negative potential.