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Microchip Technology JANS1N4993CUS/TR
- Part No.:
- JANS1N4993CUS/TR
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- SQ-MELF, E
- Datasheet:
-
JANS1N4993CUS/TR.pdf
- Description:
- DIODE ZENER 300V 5W E-MELF
- Quantity:
- Payment:
- Shipping:
Inventory:3,757
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Product details
Overview
JANS1N4993CUS/TR from Microsemi is a hermetically sealed, voidless-glass surface-mount Zener diode rated for 5 W power dissipation at 140 °C end-cap temperature, with nominal Zener voltage of 300 V ±1% (C-suffix), dynamic impedance of 950 Ω at 4 mA test current, and operating junction temperature range from –65 °C to +175 °C. It serves as a precision voltage reference and overvoltage clamp in radiation-hardened military power conditioning circuits.
For engineers reviewing the JANS1N4993CUS/TR datasheet, JANS1N4993CUS/TR pinout, JANS1N4993CUS/TR application, or JANS1N4993CUS/TR equivalent, this part is selected for high-reliability, high-temperature, radiation-tolerant voltage regulation where failure is not acceptable - especially in aerospace power supplies, missile guidance analog front-ends, and nuclear instrumentation signal conditioning.
Technical Context
This JANS1N4993CUS/TR belongs to the MIL-PRF-19500/356 qualified 1N4954US–1N4996US family and uses Category I internal metallurgical bonds with triple-layer passivation. Its voidless-glass construction ensures hermetic sealing without internal voids, critical for long-term stability under thermal cycling and vacuum environments.
The device exhibits a temperature coefficient of +0.120 %/°C at 4 mA, reverse leakage ≤2 μA at 228 V, and surge capability of 2150 A (8.3 ms square wave). It is nonsensitive to ESD per MIL-STD-750 Method 1020 and inherently radiation-hard per MicroNote 050.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 300 V ±1% at 4 mA - enables precise 300 V rail clamping or reference generation with tight tolerance. |
| Power Dissipation | 5 W @ TEC = 140 °C - supports sustained operation in high-temperature avionics enclosures without derating until 175 °C. |
| Dynamic Impedance (ZZ) | 950 Ω @ IZT = 4 mA - ensures stable regulation under moderate load transients in feedback loops. |
| Max Reverse Leakage (IR) | 2 μA @ VR = 228 V - guarantees minimal parasitic current in high-impedance bias networks. |
| Temp Coefficient (αVZ) | +0.120 %/°C @ IZT = 4 mA - quantifies predictable positive drift for thermal compensation design. |
| Surge Current (IZSM) | 2150 A @ 8.3 ms - withstands lightning-induced transients in vehicle-mounted power systems. |
| Junction Temp Range | –65 °C to +175 °C - validated for operation in space-grade cryogenic and engine-bay thermal environments. |
Pinout & Package
Package: Hermetically sealed voidless hard glass case with tungsten slugs, "E" package (also designated D-5B), surface-mount configuration with copper end caps finished in Sn/Pb. Cathode indicated by band. Weight: 539 mg.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-side connection | Connected to circuit ground or lowest potential node during Zener operation. |
| Cathode | Zener breakdown terminal / high-side connection | Connected to regulated voltage rail; marked by visible band on glass body. |
Key Features
| Feature | Design Value |
|---|---|
| Voidless hermetic glass seal | Eliminates moisture ingress and internal delamination risk over 20+ year mission life in vacuum or humid environments. |
| Category I metallurgical bond | Ensures mechanical integrity and thermal cycle reliability exceeding 1000 cycles between –65 °C and +175 °C. |
| Triple-layer passivation | Prevents surface conduction paths and ion migration under high humidity and bias stress. |
| MIL-PRF-19500/356 qualification (JANS) | Validated for Class S screening including burn-in, temperature cycling, and lot acceptance testing per military standard. |
| Nonsensitive to ESD (MIL-STD-750 Method 1020) | Withstands ≥4 kV HBM without parameter shift - simplifies handling in cleanroom assembly lines. |
Applications
| Aerospace Power Conditioning | Missile Guidance Analog Front-End |
|---|---|
Use Scenario: Regulating auxiliary 300 V bus in satellite power distribution units exposed to deep-space thermal cycling. IC Role / Device Role / Timing Role: Voltage reference and overvoltage clamp for DC-DC converter feedback and protection circuitry. Use Value: Maintains regulation accuracy within ±1% across –65 °C to +125 °C ambient, preventing false trip in fault-monitoring comparators. |
Use Scenario: Stabilizing bias voltage for op-amps and ADC drivers in inertial measurement unit (IMU) signal chains. IC Role / Device Role / Timing Role: Precision Zener reference source for ratiometric sensor excitation and offset calibration. Use Value: Delivers <2 μA leakage at 228 V, minimizing input bias error in high-impedance transducer interfaces. |
| Nuclear Instrumentation | Tactical Vehicle Power Systems |
Use Scenario: Providing stable reference in gamma-ray spectrometer high-voltage detector bias supplies. IC Role / Device Role / Timing Role: Radiation-hardened voltage clamp protecting charge-sensitive amplifiers from HV transients. Use Value: Inherent radiation hardness (per MicroNote 050) ensures no parametric shift after 100 krad(Si) total ionizing dose exposure. |
Use Scenario: Clamping induced surges on 28 V aircraft bus during load dump events in airborne radar subsystems. IC Role / Device Role / Timing Role: Transient voltage suppressor in parallel with primary regulator output stage. Use Value: Absorbs 2150 A surge (8.3 ms) without degradation, meeting MIL-STD-1275E surge immunity requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| JANTXV1N4993CUS/TR | Same electrical specs and package, but screened to JANTXV level (lower screening rigor than JANS). | Limited to non-flight-critical subsystems where full JANS Class S screening is not mandated. | Select when cost and lead time constraints outweigh need for full space-qualified screening. |
| 1N4993CUS/TR | Commercial-grade version; lacks MIL-PRF-19500/356 qualification, radiation hardness validation, and extended temperature screening. | Suitable only for ground-based industrial equipment with ambient ≤85 °C and no radiation exposure. | Use only in non-mission-critical prototypes or commercial derivatives where military specs are waived. |
Compared with JANS1N4993CUS/TR, JANTXV1N4993CUS/TR offers identical performance with reduced screening overhead, while 1N4993CUS/TR omits radiation tolerance, hermeticity verification, and extreme-temperature validation - making it unsuitable for deployed aerospace or defense hardware.
Availability
JANS1N4993CUS/TR is available at Aetrix Electronics and suitable for aerospace power conditioning, missile guidance analog front-ends, and nuclear instrumentation requiring stable component supply under extended temperature, radiation, and long-life constraints.
Supply support for JANS1N4993CUS/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) designs high-reliability analog and mixed-signal semiconductors for aerospace, defense, and industrial markets, with emphasis on radiation-hardened and high-temperature operation.
The JANS1N4993CUS/TR belongs to Microsemi's legacy MIL-PRF-19500/356 Zener diode product line, engineered specifically for voltage regulation in mission-critical systems where parametric stability under extreme environmental stress is mandatory.
FAQ
What is the Zener voltage tolerance for JANS1N4993CUS/TR?
JANS1N4993CUS/TR has a nominal Zener voltage of 300 V with ±1% tolerance, indicated by the "C" suffix per Microsemi's standard coding. This tolerance is verified at 4 mA test current and 25 °C, and remains stable across the full –65 °C to +175 °C operating range due to hermetic construction and Category I bonding.
Is JANS1N4993CUS/TR radiation-hardened?
Yes, JANS1N4993CUS/TR is inherently radiation-hardened as documented in Microsemi MicroNote 050. It exhibits no functional degradation or parametric shift after exposure to 100 krad(Si) total ionizing dose, making it suitable for satellite and nuclear instrumentation applications where radiation effects must be mitigated without shielding.
What is the maximum continuous Zener current for JANS1N4993CUS/TR?
The maximum continuous Zener current (IZM) for JANS1N4993CUS/TR is 1.0 mA, derived from its 5 W power rating and 300 V Zener voltage (P = V × I → I = 5 W / 300 V ≈ 16.7 mA). However, the datasheet specifies IZM = 1.0 mA at 25 °C, reflecting conservative derating for sustained operation at elevated temperatures up to +175 °C.
Does JANS1N4993CUS/TR require special PCB layout considerations?
Yes - JANS1N4993CUS/TR uses the "E" (D-5B) surface-mount package with center adhesive pad option. PCB land pattern must match Microsemi's recommended pad layout (SD44A.pdf, Page 4), including optional 0.080″ center contact for epoxy anchoring. Thermal relief to copper planes is recommended to manage 5 W dissipation at high ambient temperatures.
How does the voidless-glass construction of JANS1N4993CUS/TR improve reliability?
The voidless-glass construction of JANS1N4993CUS/TR eliminates internal micro-voids that could expand under thermal cycling or vacuum, preventing hermetic seal failure. Combined with tungsten slugs and Category I metallurgical bonds, it achieves >1000 thermal cycles between –65 °C and +175 °C without parameter drift or leakage increase - a key requirement for flight-qualified components.
JANS1N4993CUS/TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- SQ-MELF, E
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 300 V
- Tolerance:
- ±2%
- Power - Max:
- 5 W
- Impedance (Max) (Zzt):
- 950 Ohms
- Current - Reverse Leakage @ Vr:
- 2 µA @ 228 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.5 V @ 1 A
- Operating Temperature:
- -65°C ~ 175°C (TJ)
- Grade:
- Military
- Qualification:
- MIL-PRF-19500/356
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- E-MELF
JANS1N4993CUS/TR FAQ
1.How can I place an order for JANS1N4993CUS/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for JANS1N4993CUS/TR on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for JANS1N4993CUS/TR reliable?
The price and inventory of JANS1N4993CUS/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for JANS1N4993CUS/TR is usually 5 days.
3.What payment methods are accepted for JANS1N4993CUS/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for JANS1N4993CUS/TR transactions.
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4.How is shipping managed for JANS1N4993CUS/TR?
JANS1N4993CUS/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your JANS1N4993CUS/TR order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for JANS1N4993CUS/TR?
For technical support, including JANS1N4993CUS/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your JANS1N4993CUS/TR requirements.
6.How does Aetrix verify that JANS1N4993CUS/TR is sourced from the original manufacturer or authorized distributors?
All JANS1N4993CUS/TR products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that JANS1N4993CUS/TR meets industry standards.
7.What is the process for return or replacement of JANS1N4993CUS/TR?
All JANS1N4993CUS/TR units undergo pre-shipment inspection (PSI). If there is an issue with JANS1N4993CUS/TR, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The JANS1N4993CUS/TR part is unused and in its original packaging.
Return procedure for JANS1N4993CUS/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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