YB1518 Overview
The YB1518 is a step-up DC-DC converter; operates as current source to drive up to 6 white LEDs(VIN at 3.0V) or 8 LEDs(VIN at 3.4V) or 9 LEDs(VIN at 3.4V) in series. Series connecting of the LEDs provides identical LED currents resulting in uniform brightness and eliminating the need for ballast resistors.