The 3EZ3.9D5 series Zener diodes are 3‑watt devices with a nominal Zener voltage of 3.9 V and a maximum power dissipation of 3 W. They feature a high surge current rating, a forward voltage of 1.2 V at 200 mA, and operate over a junction temperature range of –65 °C to +175 °C.
Mechanically, the devices are supplied in a molded axial lead package (Case 4) with corrosion‑resistant, solderable leads. The thermal resistance is 45 °C/W, and each diode weighs about 0.4 g. Detailed electrical characteristics, tolerance codes, and derating curves are provided for design reference.
| Zener Voltage | 3.9 V |
|---|---|
| Maximum Power Dissipation | 3 W |
| Forward Voltage @ 200 mA | 1.2 V |
| Junction Temperature Range | -65 °C to +175 °C |
| Power Derating | 2 mW/°C above 25 °C |
| Thermal Resistance | 45 °C/W |
| Weight | 0.4 g (typical) |
| Package Type | Molded axial lead (Case 4) |
Suffix 1 indicates a +1 % tolerance on the Zener voltage.
The Zener voltage is measured by applying a test current of 40 µA plus 10 µA before reading.
The maximum surge current pulse width is 8.3 milliseconds.