The IS31FL3717-GRLS4-TR from Lumissil Microsystems is a LED Driver IC with Input Voltage 2.7 to 5.5 V, Output Current 31.8 to 37.4 mA, Operating Temperature Range -40 to 125 Degree C. Tags: Surface Mount, General Purpose LED Driver. More details for IS31FL3717-GRLS4-TR can be seen below.