Arrangement and method for operating an arrangement

摘要

A method is set up to operate an arrangement that has N radiation-emitting semiconductor chips arranged in an electric series circuit. The arrangement includes multiple switching elements, wherein to each of the semiconductor chips one of the switching elements is connected electrically in parallel. The arrangement includes a controller for the mutually independent activation of the switching elements. The arrangement includes a constant current circuit for energizing the series circuit. When switching off, the respective semiconductor chip associated with a switching element is bridged electrically by the switching element. A protective module of the arrangement is set up to reduce or to prevent current peaks when one or more of the semiconductor chips is/are switched off.

主权项

1. A lighting apparatus installed in an adaptive vehicle headlight, the apparatus comprising:
N radiation-emitting semiconductor chips coupled in an electrical series circuit, N being a natural number with N≧2; a plurality of switch elements, wherein each semiconductor chip or a group of semiconductor chips is connected in parallel with a respective one of the switch elements so that each semiconductor chip or group of semiconductor chips is electrically bypassed by the respective switch element when that semiconductor chip or group of semiconductor chips is turned off; a controller configured to activate the switch elements independently of one another; a constant current source coupled to energize the series circuit; and a protection module arranged to reduce or prevent current spikes when one or more of the semiconductor chips are turned off, wherein the semiconductor chips are activated by a pulse width modulation, wherein a nth semiconductor chip is turned on during a modulation period with a total duration T for a coherent turned on duration tn with tn≦T and nε[1;N], wherein only a part of the semiconductor chips is turned on by the protection module at a beginning of the modulation period, wherein at least one of the semiconductor chips is turned off and simultaneously another of the semiconductor chips is turned on by the protection module within the modulation period, wherein turned on durations tn are adapted to one another and shifted within the modulation period by the protection module so that at least some of the target turned on durations of the semiconductor chips output by the controller are changed by the protection module by up to 10% of the total duration T to obtain the actual turned on durations tn, and wherein a number of events is minimized, during which one of the semiconductor chips is turned off and a turning on of another semiconductor chip does no oppose this turning off so that a number of simultaneous turning-on operations and turning-off operations of the semiconductor chips is maximized.