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Microchip Technology 1N4685UR-1/TR
- Part No.:
- 1N4685UR-1/TR
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-213AA
- Datasheet:
-
1N4685UR-1/TR.pdf
- Description:
- DIODE ZENER 3.6V 500MW DO213AA
- Quantity:
- Payment:
- Shipping:
Inventory:6,244
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Product details
Overview
1N4685UR-1/TR from Microsemi is a 3.6 V, ±5% tolerance, 500 mW surface-mount Zener diode in DO-213AA (SOD-80/MLL34) MELF glass package, tested at 50 µA, with 0.95 V voltage regulation and 2.0 µA reverse leakage at 1.0 V, used for precision low-current voltage reference and biasing in space-constrained analog circuits.
For engineers reviewing the 1N4685UR-1/TR datasheet, 1N4685UR-1/TR pinout, 1N4685UR-1/TR application, or 1N4685UR-1/TR equivalent, key selection criteria include its ultra-low test current (50 µA), hermetic glass construction, metallurgical die bonding, MIL-PRF-19500 up-screening capability, and RoHS-compliant commercial-grade variant availability.
Technical Context
The 1N4685UR-1/TR operates as a two-terminal voltage regulator in reverse-bias breakdown mode, with Zener voltage specified at 3.6 V ±5% under 50 µA test current. Its low IZT enables stable regulation in micro-power circuits where supply current is limited.
It features a hermetically sealed DO-213AA glass MELF package with metallurgically bonded silicon die, delivering high reliability, radiation hardness per MicroNote 050, and ESD insensitivity per MIL-STD-750 Method 1020 - critical for aerospace and industrial control environments.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 3.6 V ±5% at 50 µA - defines precise regulation point for low-current bias networks |
| Power Dissipation (PD) | 0.5 W - supports continuous operation up to 150 mA at 3.3 V drop without derating below 50 °C ambient |
| Zener Test Current (IZT) | 50 µA - enables use in nanoamp-level bias chains without loading error |
| Reverse Leakage (IR) | 7.5 µA max at 1.0 V - ensures minimal parasitic current in standby or sleep-mode circuits |
| Voltage Regulation (∆VZ) | 0.95 V - quantifies deviation between 10 µA and 100 µA operating points, indicating knee sharpness |
| Max Zener Current (IZM) | 150 mA - derived from 0.5 W rating and 3.6 V VZ, sets absolute safe operating limit |
| Junction Temp Range | –65 °C to +175 °C - supports deployment in extended-temperature avionics and downhole electronics |
Pinout & Package
DO-213AA (SOD-80 / MLL34) MELF glass package: cylindrical hermetic body with metallized end caps; cathode indicated by single black band; no polarity-specific PCB footprint asymmetry - symmetric pad layout required.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference | Connected to lower-potential node in reverse-bias regulation; forms return path for IZ |
| Cathode | Zener breakdown terminal / regulation output | Banded end; connected to higher-potential node; delivers stable 3.6 V reference when reverse-biased |
Key Features
| Feature | Design Value |
|---|---|
| Hermetic glass MELF construction | Eliminates moisture ingress and long-term parameter drift in humid or corrosive environments |
| Metallurgical die bonding | Enables >106 thermal cycles without bond fatigue - validated for satellite power subsystems |
| Ultra-low 50 µA test current | Permits integration into sub-100 µA sensor bias rails without compromising regulation accuracy |
| MIL-PRF-19500 up-screening option | Supports qualification to Class H (JANTXV) or Class K (JANS) for flight-critical hardware |
| Non-ESD-sensitive design | Withstands >4 kV HBM without screening - reduces handling controls in production assembly |
Applications
| Reference Voltage Source | Low-Power Sensor Biasing |
|---|---|
Use Scenario: Providing stable 3.6 V reference for ADC voltage dividers and op-amp comparators in battery-powered IoT nodes. IC Role / Device Role / Timing Role: Two-terminal shunt reference establishing precise analog ground-referenced threshold. Use Value: Maintains ±0.18 V regulation over –40 °C to +85 °C with <10 µA quiescent current draw. | Use Scenario: Biasing photodiode amplifiers and MEMS oscillator circuits where supply current must stay below 50 µA. IC Role / Device Role / Timing Role: Low-current Zener acting as active load and DC offset generator in transimpedance stages. Use Value: Delivers repeatable 3.6 V node with <0.95 V regulation spread across 10 µA–100 µA operating range. |
| Aerospace Power Monitoring | Industrial Signal Conditioning |
Use Scenario: Regulating auxiliary rail for radiation-tolerant FPGA configuration memory in LEO satellites. IC Role / Device Role / Timing Role: Radiation-hardened shunt regulator protecting against TID-induced threshold shift in downstream logic. Use Value: Leverages inherent radiation hardness per MicroNote 050 and –65 °C to +175 °C junction rating. | Use Scenario: Stabilizing input thresholds of isolated analog inputs in PLC analog I/O modules. IC Role / Device Role / Timing Role: Precision clamp preventing overvoltage damage to 24 V field-side protection circuitry. Use Value: Provides 3.6 V clamping with 7.5 µA leakage at 1.0 V - avoids false triggering during transient events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4685US-1/TR | Same electrical specs; plastic SOD-123 package instead of glass DO-213AA | Lacks hermeticity and radiation hardness; unsuitable for space or high-reliability mil-aero | Select only for cost-sensitive commercial designs where environmental robustness is secondary |
| BZX55C3V6 | 3.6 V ±5%, 500 mW, but rated at 5 mA IZT; higher leakage (5 µA @ 1 V) | Requires higher bias current; less suitable for nanoamp-sleep systems | Prefer when existing 5 mA bias infrastructure exists and radiation tolerance is not required |
Compared with 1N4685US-1/TR and BZX55C3V6, the 1N4685UR-1/TR uniquely combines ultra-low 50 µA test current, hermetic glass packaging, and documented radiation hardness - making it the only choice for micro-power, high-reliability, or radiation-exposed applications.
Availability
1N4685UR-1/TR is available at Aetrix Electronics and suitable for aerospace power monitoring, low-power sensor biasing, industrial signal conditioning, and reference voltage source applications requiring stable component supply across extended temperature and radiation environments.
Supply support for 1N4685UR-1/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 Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and secure analog and mixed-signal ICs and discrete components.
The 1N4685UR-1/TR belongs to Microsemi's legacy DO-213AA Zener series designed specifically for mission-critical analog regulation in aerospace, defense, and industrial control systems where hermeticity, low-current stability, and long-term parameter retention are mandatory.
FAQ
What is the Zener voltage tolerance of the 1N4685UR-1/TR?
The 1N4685UR-1/TR has a nominal Zener voltage of 3.6 V with a standard tolerance of ±5%, as confirmed in the Electrical Characteristics table on page 3 of Microsemi's T4-LDS-0240-1 Rev. 2 datasheet. Tighter 2% and 1% tolerances are available under different part number suffixes (C and D), but the base 1N4685UR-1/TR is ±5%.
Does the 1N4685UR-1/TR require a heatsink in typical operation?
No, the 1N4685UR-1/TR does not require a heatsink under standard conditions. With a 0.5 W power rating and thermal resistance of 250 °C/W (junction-to-ambient), it remains within safe junction temperature limits (<125 °C) at ambient temperatures below 50 °C on FR4 board - verified per Maximum Ratings table on page 1 of the datasheet.
Is the 1N4685UR-1/TR RoHS compliant?
Yes, the 1N4685UR-1/TR is available in RoHS-compliant version with matte-tin plating (designated by "e3" in nomenclature), but only for commercial-grade units. The RoHS-compliant variant is explicitly noted in the Part Nomenclature section on page 2 and confirmed in the Features list on page 1 of the official datasheet.
What does the "UR-1" suffix indicate in 1N4685UR-1/TR?
The "UR-1" suffix identifies the device as a metallurgically bonded, surface-mount Zener in DO-213AA package per Microsemi's nomenclature system. "UR" denotes the internal metallurgical bond and hermetic glass construction, while "-1" indicates standard commercial screening - distinct from JAN, JANTX, or JANS variants which carry MQ/MX/MV/MSP prefixes.
Can the 1N4685UR-1/TR be used in forward-bias applications?
The 1N4685UR-1/TR is optimized for reverse-bias Zener regulation, but its forward voltage is specified as 1.5 V at 100 mA (Maximum Ratings table, page 1). While usable as a general-purpose diode, its forward characteristics are not characterized for switching or rectification - use only as a shunt regulator unless validated per application requirements.
1N4685UR-1/TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-213AA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 3.6 V
- Tolerance:
- ±5%
- Power - Max:
- 500 mW
- Impedance (Max) (Zzt):
- -
- Current - Reverse Leakage @ Vr:
- 7.5 µA @ 2 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.5 V @ 100 mA
- Operating Temperature:
- -65°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-213AA
1N4685UR-1/TR FAQ
1.How can I place an order for 1N4685UR-1/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4685UR-1/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 1N4685UR-1/TR reliable?
The price and inventory of 1N4685UR-1/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4685UR-1/TR is usually 5 days.
3.What payment methods are accepted for 1N4685UR-1/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4685UR-1/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4685UR-1/TR?
1N4685UR-1/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4685UR-1/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 1N4685UR-1/TR?
For technical support, including 1N4685UR-1/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4685UR-1/TR requirements.
6.How does Aetrix verify that 1N4685UR-1/TR is sourced from the original manufacturer or authorized distributors?
All 1N4685UR-1/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 1N4685UR-1/TR meets industry standards.
7.What is the process for return or replacement of 1N4685UR-1/TR?
All 1N4685UR-1/TR units undergo pre-shipment inspection (PSI). If there is an issue with 1N4685UR-1/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 1N4685UR-1/TR part is unused and in its original packaging.
Return procedure for 1N4685UR-1/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4685UR-1/TR Tags
-
MMBZ5240B-7-F
Diodes Incorporated
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BZT52C5V6T-7
Diodes Incorporated
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MMSZ5231B-7-F
Diodes Incorporated
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BZT52C15-7-F
Diodes Incorporated
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BZX84C3V3LT1G
onsemi
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MMSZ5245BS-7-F
Diodes Incorporated
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MMSZ4682T1G
onsemi
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BZT52C15S-7-F
Diodes Incorporated
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MM5Z5V1ST1G
onsemi
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SMAJ4744A-TP
Micro Commercial Co
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BZT52C3V6LP-7
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SMAZ12-13-F
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