This part is a kind of semiconductor called BRF91.

Function of this product has RF NPN Transistor.

Manufacturers : Microsemi Corporation

Image and pinout :

Some of the text within the PDF file :

140 COMMERCE DRIVE MONTGOMERYVILLE, PA 18936-1013 PHONE: (215) 631-9840 FAX: (215) 631-9855 BFR91 RF & MICROWAVE DISCRETE LOW POWER TRANSISTORS Features • • • High Current-Gain – Bandwidth Product, fT = 5 GHz (typ) @ IC = 30 mA Low Noise Figure – NF = 1.9 dB (typ) @ f = 0.5 GHz, 2.5 dB (typ) @ 1GHz High Power Gain – Gmax = 16 dB (typ) @ f = 0.5 GHz, 10.9dB (typ) @ 1GHz Macro T (STYLE #2) DESCRIPTION: Designed primarily for use in high-gain, low noise, small-signal amplifiers. Also used in applications requiring fast switching times. ABSOLUTE MAXIMUM RATINGS (Tcase = 25°C) Symbol VCEO VCBO VEBO IC Parameter Collector-Emitter Voltage Collector-Base Voltage Emitter-Base Voltage Collector Current Value 12 15 3.0 35 Unit Vdc Vdc Vdc mA Thermal Data P D Total Device Dissipatio [ ... ]

BRF91 PDF Datasheet Download