Abstract: A LED retrofit driver circuit (3) is provided, comprising at least an input (6) for receiving an operating voltage from a power supply (2), an output (8) for connection to one or more LED units (5), a power converter (7) connected with said input (6) and said output (8) and configured to provide a lamp current (50) at said output (8) during operation in at least a first and a second operating state. To provide a versatile circuit (3), allowing operation with a variety of power supplies and under various load conditions, in said first operating state, the power converter (7) is adapted to switch between a high current generating mode (40), in which the power converter (7) is configured to draw current pulses from said power supply (2) to provide a first average input current (33a), and an OFF mode (42) in which no current is drawn from said power supply (2).

Abstract: A LED retrofit driver circuit (3) is provided, comprising at least an input (6) for receiving an operating voltage from a power supply (2), an output (8) for connection to one or more LED units (5), a power converter (7) connected with said input (6) and said output (8) and configured to provide a lamp current (50) at said output (8) during operation in at least a first and a second operating state. To provide a versatile circuit (3), allowing operation with a variety of power supplies and under various load conditions, in said first operating state, the power converter (7) is adapted to switch between a high current generating mode (40), in which the power converter (7) is configured to draw current pulses from said power supply (2) to provide a first average input current (33a), and an OFF mode (42) in which no current is drawn from said power supply (2).

Abstract: An illumination device (1) comprises: at least one low-power light source (50); a power input stage (20) suitable for receiving AC low voltage from an electronic transformer (ET); a power buffer stage (30) having an input (31) connected to the input stage output (29); a driver (40) for driving the light source and receiving electric power supply from the power buffer stage. The power input stage generates output current pulses for charging the power buffer stage at a relatively low frequency, and during each output current pulse, the power input stage draws input current, the input current always having a current magnitude higher than a minimum load requirement of the electronic transformer.

Abstract: An illumination device (1) comprises: at least one low-power light source (50); a power input stage (20) suitable for receiving AC low voltage from an electronic transformer (ET); a power buffer stage (30) having an input (31) connected to the input stage output (29); a driver (40) for driving the light source and receiving electric power supply from the power buffer stage. The power input stage generates output current pulses for charging the power buffer stage at a relatively low frequency, and during each output current pulse, the power input stage draws input current, the input current always having a current magnitude higher than a minimum load requirement of the electronic transformer.