This part is a kind of semiconductor called 1N5374B.

Function of this product has 40 Zener Voltage Regulators.

Manufacturers : ON Semiconductor

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1N53 Series 5 Watt Surmetict 40 Zener Voltage Regulators This is a complete series of 5 Watt Zener diodes with tight limits and better operating characteristics that reflect the superior capabilities of silicon−oxide passivated junctions. All this in an axial lead, transfer−molded plastic package that offers protection in all common environmental conditions. Features • Zener Voltage Range − 3.3 V to 200 V • ESD Rating of Class 3 (>16 kV) per Human Body Model • Surge Rating of up to 180 W @ 8.3 ms • Maximum Limits Guaranteed on up to Six Electrical Parameters • Pb−Free Packages are Available* Mechanical Characteristics CASE: Void free, transfer−molded, thermosetting plastic FINISH: All external surfaces are corrosion resistant and leads are readily solderable MAXIMUM LE [ ... ]

1N5374B PDF Datasheet Download