The SP6699 is an inductor-based DC/DC converter designed to drive up to five white LEDs in series for LCD modules and keypad backlighting functions. Only one feedback resistor is needed to control the LED current and obtain the desired brightness. A 1.0MHz constant frequency PWM control scheme is used, enabling the usage of small external components. A typical application needs a 1mm tall inductor and a 0.22μF output capacitor. Additionally, the boost circuit Schottky diode is integrated, further reducing the overall foot print. A logic controlled enable pin allows this device to be placed in a low current consumption mode of a few microamps. Furthermore, the SP6699 is equipped with an over voltage output protection circuit which clamps the output voltage to 27 volts when any LED fails or in other abnormal conditions.
