This part is a kind of semiconductor called ATSAMD21J18A-MUT.

Function of this product has SMART ARM-Based Microcontroller.

Manufacturers : Atmel

Image and pinout :

Some of the text within the PDF file :

SMART Atmel SAM D21E / SAM D21G / SAM D21J SMART ARM-Based Microcontroller DATASHEET Description The Atmel® | SMART™ SAM D21 is a series of low-power microcontrollers using the 32-bit ARM® Cortex®-M0+ processor, and ranging from 32- to 64-pins with up to 256KB Flash and 32KB of SRAM. The SAM D21 devices operate at a maximum frequency of 48MHz and reach 2.46 CoreMark/MHz. They are designed for simple and intuitive migration with identical peripheral modules, hex compatible code, identical linear address map and pin compatible migration paths between all devices in the product series. All devices include intelligent and flexible peripherals, Atmel Event System for inter-peripheral signaling, and support for capacitive touch button, slider and wheel user interfaces. The Atmel SAM D21 de [ ... ]

ATSAMD21J18A-MUT PDF Datasheet Download