The 50 watt zener diodes are high power zener diodes from Microsemi company. They provide voltage regulation in a selection over a 3.9 v to 200 v broad range of voltages. They can be operated up to 50 watts with adequate mounting and heat sinking with their low thermal resistance. These zeners are also available in JAN, JANTX, JANTXV military qualifications. Microsemi also offers numerous other zener products to meet higher and lower power applications.
The Microsemi 1N2804‑1N2846B and 1N4557‑1N4564B series are high‑power 50 W Zener diodes offering voltage regulation from 3.9 V to 200 V. They are available in standard anode‑to‑case polarity and a reverse‑polarity version indicated by an “R” suffix.
The document provides detailed electrical specifications, thermal characteristics, mechanical dimensions, and packaging information for the TO‑3 (TO‑204AD) hermetically sealed case. It also lists tolerance codes (A, B, C, D) and notes on military‑grade qualifications (JAN, JANTX, JANTXV).
| Zener Voltage Range | 3.9 V to 200 V |
|---|---|
| Maximum Power Dissipation | 50 W at Tc < 75 °C |
| Thermal Resistance | 2.0 °C/W max (junction‑to‑base 1.5 °C/W typical) |
| Junction Temperature Range | -65 °C to +175 °C |
| Storage Temperature Range | -65 °C to +200 °C |
| Forward Voltage @ 10 A | 1.5 V |
The diodes can dissipate up to 50 W when the case temperature is below 75 °C.
They are housed in an industry‑standard TO‑3 (TO‑204AD) hermetically sealed case.
A suffix “R” in the part number denotes cathode‑to‑case (reverse) polarity.
Suffix B gives ±5 %, A gives ±10 %, no suffix gives ±20 %, while C and D provide tighter tolerances of ±2 % and ±1 % respectively.