This part is a kind of semiconductor called BA159.

Function of this product has 1.0 AMP FAST RECOVERY RECTIFIERS.

Manufacturers : Bytes

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BA157 THRU BA159 1.0 AMP FAST RECOVERY RECTIFIERS VOLTAGE RANGE 400 to 1000 Volts CURRENT FEATURES * Low forward voltage drop * High current capability * High reliability * High surge current capability 1.0 Ampere DO-41 .107(2.7) .080(2.0) DIA. 1.0(25.4) MIN. MECHANICAL DATA * Case: Molded plastic * Epoxy: UL 94V-0 rate flame retardant * Lead: Axial leads, solderable per MIL-STD-202, method 208 guranteed * Polarity: Color band denotes cathode end * Mounting position: Any * Weight: 0.34 grams .205(5.2) .166(4.2) .034(.9) .028(.7) DIA. 1.0(25.4) MIN. Dimensions in inches and (millimeters) MAXIMUM RATINGS AND ELECTRICAL CHARACTERISTICS Rating 25 C ambient temperature uniess otherwies specified. Single phase half wave, 60Hz, resistive or inductive load. For capacitive load, derate curr [ ... ]

BA159 PDF Datasheet Download