This part is a kind of semiconductor called AS218-321.

Function of this product has PHEMT GaAs IC High Power Transfer Switch.

Manufacturers : ETC

Image and pinout :

Some of the text within the PDF file :

DATA SHEET AS218-321, AS218-321LF: PHEMT GaAs IC High Power Transfer Switch DC–6 GHz Applications ● QFN-12 0.118 (3.00 mm) 0.008 (0.20 mm) Seating Plane 0.001 (0.02 mm) 0.118 (3.00 mm) Pin 1 Indicator WLAN 802.11a, b, g diversity Features ● ● ● ● ● Operating frequency DC–6 GHz Positive low voltage control (0/+3 V operation) Low insertion loss PHEMT process Available lead (Pb)-free MSL-1 @ 250 °C per JEDEC J-STD-020 0.029 (0.73 mm) Exposed pad 0.007 (0.180 mm) 0.030 (0.75 mm) ± 0.002 (0.05 mm) 0.017 (0.435 mm) Sq. Pin 1 Indicator Description The AS218-321 is a broadband transfer switch designed to combine T/R and antenna diversity switching functions on a single IC. The device is designed to handle high power and maintain high linearity at low control voltages. Thi [ ... ]

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