DIRECTLY DRIVEN HIGH EFFICIENCY LED CIRCUIT

摘要

A system for directly driving light emitting diodes (LEDs). A string of LEDs is coupled across an input voltage and includes a plurality of separate groups of LEDs. Each of a plurality of switches is coupled in parallel with an associated one of the groups of LEDs for controlling current flow through the associated group of LEDs in response to a control signal from a controller circuit. A switch protection circuit is associated with at least one of the switches. The switch protection circuit is configured to place the switch into a conducting state in the event of failure of an LED in the associated group of LEDs.