This part is a kind of semiconductor called AS3990.

Function of this product has UHF RFID single chip reader EPC Class1 Gen2 compatible.

Manufacturers : austriamicrosystems AG

Image and pinout :

Some of the text within the PDF file :

PRELIMINARY INFORMATION: SUBJECT TO CHANGE WITHOUT ANY NOTICE Data Sheet AS3977 UHF RFID single chip reader EPC Class1 Gen2 compatible AS3990 General Description The AS3990 UHF reader chip is an integrated analogue front end and data framing system for a 900MHz RFID reader system. Built in programming options make it suitable for a wide range of applications in UHF RFID systems. Designed to simplify the design and implementation of an EPC Class 1Gen2 reader, this IC requires only a standard 8Bit microcontroller with minimal other components. The AS3990 comprises the EPC Class 1- Gen2 protocol (ISO 18000-6c) with digital high speed logic up to the framing level and supports the ISO 180006a and ISO 18000-6b Protocol with direct data mode. The Interface to the microcon [ ... ]

AS3990 PDF Datasheet Download