A high efficiency white LED driver that guarantees matching LED brightness is described.
White LED driver
White LEDs are widely used in small LCD backlight applications for simplicity, high reliability and low cost. However, due to variations in the forward voltage drop of white LEDs, matching the brightness becomes a major design consideration for multiple LED applications. Since LED brightness is proportional to current rather than voltage, a constant-current source driving LEDs in series should be used to ensure the same illumination of each LED. The LT1932 uses a constant-current step-up ...