It is packaged in Tape & Reel (TR). As a space-saving measure, it is included in the 48-VFQFN Exposed Pad package. Surface Mount instructs that it should be mounted in the following manner. As long as -40°C~85°C TA is maintained, the device should function properly.
ISL68137IRBZ-TR5781 Features
48-VFQFN Exposed Pad package Mounting type of Surface Mount
ISL68137IRBZ-TR5781 Applications
There are a lot of Renesas Electronics America Inc. ISL68137IRBZ-TR5781 Power Supply Control ICs applications.