This part is a kind of semiconductor called 1N4773.

Function of this product has TEMPERATURE COMPENSATED ZENER DIODES.

Manufacturers : Digitron Semiconductors

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1N4765(A)-1N4774(A) High-reliability discrete products and engineering services since 1977 TEMPERATURE COMPENSATED ZENER DIODES FEATURES  Available as “HR” (high reliability) screened per MIL-PRF-19500, JANTX level. Add “HR” suffix to base part number.  Available as non-RoHS (Sn/Pb plating), standard, and as RoHS by adding “-PBF” suffix. MAXIMUM RATINGS Characteristics Operating and storage temperature DC power dissipation Power derating IR = 10µA @ 25°C and VR = 6V Values -65 to +175°C 500mW @ 50°C 4mW/°C above 50°C ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise specified) Zener voltage Zener test current Maximum dynamic impedance Part number VZ @ IZT (Note 3) IZT ΔZZT (Note 1) Maximum voltage temperature stability VZT (Note 2) Temperature [ ... ]

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