Description
IS31LT3938 LED driver IC is a peak current detection buck converter which operates in constant off time mode. It operates over a very wide input voltage supply range of 10VDC to 450VDC or 110VAC/220VAC. IS31LT3938 incorporates the special feature of three power sequencing levels by detecting OFF-ON cycles of the main power switch. When the switch is cycled within a 4 second period (typical) the device automatically switches the power level to the next step. As a result, the input and output power of the luminaire may be adjusted depending on the desired amount of illumination and/or power consumption. There are multiple power levels that the engineer may configure, 2 steps or 3 steps, via the external pins DIM1 and DIM2.

FEATUREs
● User configurable power sequencing levels
● 3% output current accuracy
● Over current, temperature protection and short circuit
   protection
● High efficiency (typical up to 95%)
● Higher MOS drive voltage
● Wide input voltage range: 10VDC~450VDC or
   85Vac~ 265Vac
● Linear and PWM dimming
● Very few external components

APPLICATIONs
● DC/DC or AC/DC constant current LED driver
● Signal and decorative lighting
● Backlight LED driver