Microchip Technology JANTXV1N4993CUS/TR

Overview

JANTXV1N4993CUS/TR from Microsemi is a military-grade, hermetically sealed surface-mount Zener diode rated for 5 W power dissipation, with a nominal Zener voltage of 300 V at 4 mA test current, ±1% tolerance (C suffix), and operating junction temperature range of –65 °C to +175 °C. It serves as a precision voltage reference and overvoltage clamp in high-reliability power regulation circuits for aerospace and defense systems.

For engineers reviewing the JANTXV1N4993CUS/TR datasheet, JANTXV1N4993CUS/TR pinout, JANTXV1N4993CUS/TR application, or JANTXV1N4993CUS/TR equivalent, this part is selected for ultra-stable voltage regulation under extreme thermal stress, radiation exposure, and long-term mission-critical operation where failure is not an option.

Technical Context

This device belongs to the MIL-PRF-19500/356 qualified 1N4954US–1N4996US family and uses voidless hermetically sealed hard-glass construction with internal Category I metallurgical bonds. Its Zener breakdown mechanism delivers stable regulation across 10%–50% of IZM (28 mA), with dynamic impedance of 950 Ω at IZT and <2 μA reverse leakage at VR = 228 V.

The "E" package (D-5B) features tungsten slugs and copper end caps with Sn/Pb finish, enabling direct solder attachment without adhesive. Thermal resistance is 7 °C/W junction-to-end-cap, supporting 5 W dissipation at TEC = 140 °C with linear derating to zero at 175 °C.

Key Specifications

Pinout & Package

Package: Hermetically sealed voidless hard-glass "E" package (also designated D-5B), with tungsten slugs and copper end caps finished with Sn/Pb. Cathode indicated by band. No marking on body. Weight: 539 mg.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener voltage regulation applications.

Compared with JANTXV1N4993CUS/TR, JANTXV1N4993DUS/TR offers tighter tolerance at higher cost and longer lead time, while 1N4993US sacrifices military qualification and radiation hardness for lower unit price and broader commercial availability.

Availability

JANTXV1N4993CUS/TR is available at Aetrix Electronics and suitable for aerospace power conditioning, defense radar bias supply, and satellite solar array regulator applications requiring stable component supply across extended product lifecycles and stringent environmental compliance.

Supply support for JANTXV1N4993CUS/TR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Microsemi (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog and mixed-signal components for aerospace, defense, and industrial markets.

The JANTXV1N4993CUS/TR belongs to Microsemi's MIL-PRF-19500/356 qualified Zener diode product line, engineered for voltage regulation and overvoltage protection in mission-critical systems operating under extreme thermal, mechanical, and radiation stress.

FAQ

What is the Zener voltage tolerance of JANTXV1N4993CUS/TR?

JANTXV1N4993CUS/TR has a nominal Zener voltage of 300 V with ±1% tolerance, confirmed by the "C" suffix in the part number per Microsemi SD44A datasheet. This tolerance applies at I_ZT = 4 mA and 25 °C ambient, and remains stable across the full –65 °C to +175 °C junction temperature range. The JANTXV1N4993CUS/TR achieves this via precision diffusion and post-trim validation during manufacturing.

Does JANTXV1N4993CUS/TR require heatsinking in 5 W operation?

JANTXV1N4993CUS/TR is rated for 5 W dissipation at T_EC = 140 °C without external heatsinking, relying on its 7 °C/W junction-to-end-cap thermal resistance and direct PCB copper pad conduction. Heatsinking is unnecessary if the end-cap is soldered to ≥1 in² of 2-oz copper with thermal vias; exceeding 5 W or operating above 140 °C requires derating per the linear curve in the SD44A datasheet.

Is JANTXV1N4993CUS/TR radiation hardened?

Yes, JANTXV1N4993CUS/TR is inherently radiation hard, documented in Microsemi MicroNote 050 for total ionizing dose (TID) tolerance exceeding 100 krad(Si). This hardness arises from its voidless hermetic glass package and Category I metallurgical bond structure-not added shielding-making it suitable for LEO and MEO satellite power systems without additional rad-hard qualification testing.

What is the maximum reverse leakage current for JANTXV1N4993CUS/TR?

The maximum reverse leakage current for JANTXV1N4993CUS/TR is 2 μA at V_R = 228 V and 25 °C, as specified in the Electrical Characteristics table of SD44A. This value increases to ≤5 μA at 125 °C junction temperature. Low leakage preserves accuracy in high-impedance reference divider networks and reduces standby power loss in battery-backed systems using JANTXV1N4993CUS/TR.

Can JANTXV1N4993CUS/TR be used in place of JANTXV1N4993DUS/TR?

JANTXV1N4993CUS/TR can substitute for JANTXV1N4993DUS/TR only if ±1% Zener voltage tolerance meets system specification; the "D" suffix denotes ±0.5% tolerance, which JANTXV1N4993CUS/TR does not meet. Both share identical package, thermal specs, and MIL-PRF-19500 qualification, but JANTXV1N4993CUS/TR is not a drop-in replacement where tighter regulation is required-design validation is mandatory before substitution.