The SC446 is a high-e ciency multiple string WLED driver with an integrated boost converter. It operates over a wide input range from 4.5V to 27V with a maximum output voltage of 36V and a 2.5A internal power switch. It can drive up to thirty WLEDs in 3 strings with current up to 100mA per string. The string-to-string current matching is 2% typical, 3% maximum. The overall e ciency is greater than 90% due to the low current sense voltage and a low-impedance internal power switch. The wide PWM dimming range boasts a ratio of 500: 1. The 700kHz switching frequency enables the user to optimize the external component sizes for e ciency. When there are fewer than 10 LEDs in each string, users can adjust the output voltage protection yielding an allowable reduction in associated costs, size and voltage ratings of the output capacitor.