SMBJ5339B

SMBJ5339B is a 5 W Zener diode from Zhuhai HongJiaCheng in DO-214AA (SMB), verified against the maker’s own Zener manual — not the Ruilon SMBJ TVS documentation that covers other SMBJ rows in this catalog. One correction matters before anything else: the candidate pool printed this code at 5.1 V, but 5.1 V is the SMBJ5338B row above it in the same manual; the SMBJ5339B row reads a nominal Zener voltage of 5.6 V at a 220 mA test current, and this page follows the manual. Verified figures for this row: dynamic impedance of 1.0 Ω maximum, reverse leakage of 1.0 µA maximum at 2.0 V, maximum regulator current of 865 mA and power dissipation of 5,000 mW. Selection advice: a 5.6 V, 5 W-class Zener in SMB is a shunt-regulation and clamp choice for low-voltage rails; confirm the operating current keeps the knee impedance in the range your regulation budget assumes, since the 1.0 Ω figure is specified at the 220 mA test point. Parameters verified against the HongJiaCheng Zener diode manual (SMBJ5339B row).