摘要 |
The invention relates to an operating circuit for at least one LED, to which circuit a direct voltage or a rectified alternating voltage is fed and which provides a supply voltage for at least one LED by means of a coil (L1) and a first switch (S1) clocked by means of a control unit (SR), wherein energy, which is discharged via a diode (D1) and via at least one LED when the first switch (S1) is switched off, is interim-stored in the coil (L1) when the first switch (S1) is switched on. The control unit (SR) monitors the current through the coil (L1) during the on-time of the first switch (S1) and opens the switch (S1) if a defined first reference current (Ref1) is exceeded. The control unit (SR) subsequently detects when demagnetization of the coil (L1) has been achieved. The switch (S1) is again closed upon recognition that demagnetization of the coil (L1) has been achieved, and the switch (S1) opens when a defined second reference current (Ref2) through the switch (S1) has been exceeded during the on-time of the switch (S1), and subsequently the detection of the achievement of demagnetization of the coil (L1) is deactivated for a predetermined pause period. |