This part is a kind of semiconductor called BCY58.

Function of this product has LOW NOISE AUDIO AMPLIFIERS.

Manufacturers : STMicroelectronics

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Some of the text within the PDF file :

BCY58 BCY59 LOW NOISE AUDIO AMPLIFIERS DESCRIPTION The BCY58 and BCY59 are silicon planar epitaxial NPN transistors in Jedec TO-18 metal case. They are intended for use in audio input stages, driver stages and low-noise input stages. The complementary PNP types are respectively the BCY78 and BCY79. TO-18 INTERNAL SCHEMATIC DIAGRAM ABSOLUTE MAXIMUM RATINGS Value Symbol V CES V CEO V EBO IC IB Pt o t T s t g, T j January 1989 Parameter Collector-emitter Voltage (V BE = 0) Collector-emitter Voltage (I B = 0) Emitter-base Voltage (I C = 0) Collector Current Base Current Total Power Dissipation at T amb ≤ 25 °C at T c as e ≤ 45 °C Storage and Junction Temperature BCY58 32 32 7 200 50 0.39 1 – 65 to 200 BCY59 45 45 Unit V V V mA mA mW W °C 1/6 BCY58-BCY59 THERMAL DATA R t h j- cas e [ ... ]

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