This is a 3.3V DC/DC regulator, specifically a Murata OKI-78SR-3.3/1.5-W36-C.

They’re highly efficient (~85%) and provide 3.3V @ 1.5A (4.95W) from a 7V to 36V input.

It’s ideal if you need to produce 3.3V from a higher voltage power source for your project.

We also stock similar 5V and 12V regulators.

Features

• 7 – 36V Input
• 3.3V @ 1.5A Output (4.95W)
• < 40 mV peak-to-peak ripple
• Vertical mount, small footprint package
• No heat sink direct replacement for 3-terminal 78xx-series linear regulators
• High efficiency (~85%) with no external components
• Short circuit protection
• Outstanding thermal derating performance
• UL/EN/IEC 60950-1, 2nd Edition safety approvals

Datasheet

• Download the datasheet here