LT3599 pdf datasheet (4-Channe

The LT®3599 is a fi xed frequency 2A step-up DC/DC
converter designed to drive four strings of 100mA LEDs
up to a 44V output voltage. The switching frequency
is programmable from 200kHz to 2.5MHz through an
external resistor.
LED dimming can be achieved with analog 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.
The LT3599 is available in the thermally enhanced 32-pin
(5mm × 5mm) QFN and 28-pin TSSOP packages.