This part is a kind of semiconductor called MRF581.

Function of this product has NPN SILICON RF TRANSISTOR.

Manufacturers : ASI

Image and pinout :

Some of the text within the PDF file :

MRF581 NPN SILICON RF TRANSISTOR DESCRIPTION: The MRF581 is Designed for High current low Power Amplifier Applications up to 1.0 GHz. PACKAGE STYLE Dim. Are in mm FEATURES: • Low Noise Figure • Low Intermodulation Distortion • High Gain • Omnigold™ Metalization System MAXIMUM RATINGS IC 200 mA VCBO 36 V VCEO 18 V VEBO 2.5 V PDISS 2.5 W @ TC = 25 °C TJ -65 °C to +200 °C TSTG -65 °C to +200 °C Leads 1 and 3 = Emitter 2 = Collector 4 = Base CHARACTERISTICS TC = 25 °C SYMBOL NONETEST CONDITIONS BVCBO IC = 1.0 mA BVCEO IC = 1.0 mA BVEBO IE = 100 µA IEBO VEB = 2.0 V ICBO VCB = 15 V hFE VCE = 5.0 V IC = 50 mA MINIMUM TYPICAL MAXIMUM 36 18 2.5 100 100 50 200 UNITS V V V µA µA --- Ccb VCB = 10 V f = 1.0 MHz 1.4 2.0 pF GP VCC = 10 V IC = 50 [ ... ]

MRF581 PDF Datasheet Download