This is one piece of New Hittite Microwave 1.5-4.5GHz GaAs MMIC Schottky Dode Double-Balanced Mixer, Part Number: HMC213MS8 in MSOP8 Package.
General Spec for HM213MS8:
Spec see Data Sheet at:
http://shpat.com/docs/hittite/hmc213ms8.pdf
PCB Designed for this mixer: