This part is a kind of semiconductor called 1N4454.

Function of this product has High Conductance Ultra Fast Diode.

Manufacturers : Fairchild Semiconductor

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Some of the text within the PDF file :

1N4454 Discrete POWER & Signal Technologies 1N4454 DO-35 High Conductance Ultra Fast Diode Sourced from Process 1R. See MMBD1201-1205 for characteristics. Absolute Maximum Ratings* Symbol W IV IO IF if if(surge) Working Inverse Voltage Average Rectified Current DC Forward Current Recurrent Peak Forward Current TA = 25°C unless otherwise noted Parameter Value 50 200 400 600 1.0 4.0 -65 to +200 175 Units V mA mA mA A A °C °C Tstg TJ Peak Forward Surge Current Pulse width = 1.0 second Pulse width = 1.0 microsecond Storage Temperature Range Operating Junction Temperature *These ratings are limiting values above which the serviceability of any semiconductor device may be impaired. NOTES : 1) These ratings are based on a maximum junction temperature of 200 degrees C. 2) These are [ ... ]

1N4454 PDF Datasheet Download