This part is a kind of semiconductor called 1N829.

Function of this product has TEMPERATURE COMPENSATED ZENER REFERENCE DIODE.

Manufacturers : Digitron Semiconductors

Image and pinout :

Some of the text within the PDF file :

1N821-1N829A High-reliability discrete products and engineering services since 1977 TEMPERATURE COMPENSATED ZENER REFERENCE DIODE 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 Operating and storage temperature range DC power dissipation Solder temperatures -65°C to +175°C 500mW @ TL = 25°C and maximum current lZM OF 70mA. For optimum voltage-temperature stability, lZ = 7.5mA (less than 50 mW in dissipated power) 260°C for 10 s (max) ELECTRICAL CHARACTERISTICS (TA = 25°C unless otherwise specified) Part number Zener voltage (Note 1 and 4) VZ @ lZT Zener Test Current lZT Maximum z [ ... ]

1N829 PDF Datasheet Download