A driver for a white LED string or a display is provided. The driver
includes a boost converter that is arranged to provide an output voltage
from a source voltage. Also, the driver includes a sense resistor that is
coupled between the output voltage and a feedback voltage. The sense
resistor is coupled in series with the white LED string or the display.
Further, the boost converter uses the sense voltage across the sense
resistor to regulate the output voltage. In one embodiment, the boost
converter includes a level shifter that converts the sense voltage into a
comparison signal that is referenced to ground. In another embodiment,
the converter employs a reference voltage that is referenced to the
output voltage.