Patent ID: 8395331

Claim:
An electronic circuit for preventing a dropout of a light-emitting diode (LED) current, comprising: at least one LED; a first circuit for receiving a reference voltage and set-point current data and for using the reference voltage and the set-point current data to produce a threshold voltage; a second circuit electrically connected to the first circuit and the at least one LED, the second circuit receiving the threshold voltage, converting the threshold voltage into an output current, and providing the output current to the at least one LED, the second circuit comprising a comparator for comparing the threshold voltage to an output voltage corresponding to the output current and providing an output indicative of the relationship between the threshold voltage and the output voltage; and a logic controller electrically connected to the first and second circuits, the logic controller receiving the output of the comparator and providing second set-point current data to the first circuit if the output of the comparator indicates that the second circuit has not provided the output current, as set by the set-point current data; wherein, if the second set-point current data is provided to the first circuit, then the first circuit uses the second set-point current data to produce a second threshold voltage, and the second circuit converts the second threshold voltage into a second output current and provides the second output current to the at least one LED, the second output current being less than the output current.