The LT3599EUH#PBF is a fixed frequency step-up DC/DC Converter designed to drive four strings of 120mA LEDs up to a 44V output voltage. The switching frequency is programmable from 200kHz to 2.1MHz through an external resistor. LED dimming can be achieved with analogue dimming on the CTRL pin and with pulse width modulation dimming on the PWM pin. The LT3599 accurately regulates LED current even when the input voltage is higher than the LED output voltage. Additional features include programmable LED current derating, switching frequency synchronization to an external clock, LED string disable control, OPENLED\ alert pin, SHORTLED\ alert pins and programmable maximum output voltage when all LED strings are disconnected.