My Inquiry
My Account
Microchip Technology 1N4739UR-1/TR
- Part No.:
- 1N4739UR-1/TR
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-213AB, MELF (Glass)
- Datasheet:
-
1N4739UR-1/TR.pdf
- Description:
- DIODE ZENER 9.1V 1W DO213AB
- Quantity:
- Payment:
- Shipping:
Inventory:8,274
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1N4739UR-1/TR from Microsemi is a surface-mount 1.0 W glass-encapsulated Zener diode with nominal Zener voltage of 9.1 V, ±5% tolerance (A-suffix), 5.0 Ω dynamic impedance at 28 mA test current, and maximum reverse current of 7 µA at 7.3 V. It operates from –65°C to +175°C and is used for precision voltage regulation in high-density power supply feedback loops and reference circuits.
For engineers reviewing the 1N4739UR-1/TR datasheet, 1N4739UR-1/TR pinout, 1N4739UR-1/TR application, or 1N4739UR-1/TR equivalent, key selection criteria include Zener voltage stability over temperature, low dynamic impedance for tight regulation, hermetic DO-213AB package suitability for high-reliability environments, and RoHS-compliant (e3) termination options.
Technical Context
This device belongs to the 1N47xxAUR family of surface-mount Zener diodes electrically equivalent to through-hole 1N47xxA parts but packaged in JEDEC DO-213AB glass MELF. It delivers stable regulation across 1 mA to 500 mA operating current range with specified knee impedance (ZZK = 100 Ω at IZK = 0.5 mA) and low capacitance.
The 1N4739UR-1/TR uses a hermetically sealed glass body with tin-lead or matte-tin plating, enabling operation up to 175°C junction temperature and inherent radiation hardness per MicroNote 050. Its thermal resistance is 130°C/W junction-to-ambient on FR4 with recommended footprint.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 9.1 V ±5% at 28 mA - defines precise regulation point for feedback networks |
| Power Dissipation | 1.0 W at TEC < 125°C - supports continuous operation in compact layouts without forced cooling |
| Dynamic Impedance (ZZT) | 5.0 Ω at IZT = 28 mA - ensures minimal output voltage variation under load transients |
| Reverse Current (IR) | 7 µA max at VR = 7.3 V - guarantees low leakage in standby and precision reference paths |
| Operating Temperature | –65°C to +175°C - enables deployment in aerospace, downhole, and industrial control systems |
| Thermal Resistance | 130°C/W junction-to-ambient on FR4 - informs PCB copper area and layout requirements for thermal management |
| Forward Voltage | 1.2 V max at 200 mA - confirms low conduction loss when used in bidirectional protection or clamp configurations |
Pinout & Package
Package: DO-213AB glass MELF - hermetically sealed, leadless cylindrical surface-mount package with cathode band marking; dimensions: A = 2.39–2.66 mm, B = 4.80–5.20 mm, C = 0.41–0.55 mm; weight: 0.05 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Zener regulation terminal | Connected to higher potential side during regulation; polarity must be observed to avoid forward conduction |
| Anode (unbanded end) | Reference/return terminal | Provides return path for Zener current; tied to ground or lower-potential node in shunt regulator topology |
Key Features
| Feature | Design Value |
|---|---|
| Hermetic glass MELF construction | Enables operation at 175°C and provides intrinsic radiation hardness per MicroNote 050 |
| Low dynamic impedance (5.0 Ω) | Minimizes output voltage deviation under varying load currents in feedback loops |
| ±5% Zener voltage tolerance (A-suffix) | Meets standard precision requirements without requiring post-manufacture trimming |
| RoHS-compliant (e3) termination | Supports lead-free assembly with 260°C/10 s soldering profile compatibility |
| High reliability screening options | MIL-PRF-19500 qualified variants available (JAN/JANTXV/JANS) for mission-critical applications |
Applications
| Switch-Mode Power Supply Feedback | Industrial Sensor Reference |
|---|---|
Use Scenario: Regulates error amplifier input in isolated flyback or forward converter feedback networks. IC Role / Device Role / Timing Role: Shunt voltage reference providing stable 9.1 V threshold for optocoupler-driven control loop. Use Value: Low ZZT ensures <±15 mV output shift across 10–100% load, improving overall voltage regulation accuracy. |
Use Scenario: Supplies stable bias voltage to analog front-end circuitry in pressure or temperature transducers. IC Role / Device Role / Timing Role: Precision voltage reference for ADC reference divider or op-amp bias network. Use Value: Hermetic DO-213AB package maintains calibration integrity over –40°C to +125°C industrial temperature range. |
| Aerospace Power Conditioning | Medical Diagnostic Equipment |
Use Scenario: Provides regulated rail for FPGA configuration memory and interface logic in satellite power subsystems. IC Role / Device Role / Timing Role: Radiation-hardened voltage clamp protecting downstream ICs from transient overvoltage events. Use Value: Inherent radiation hardness and MIL-qualified screening options support DO-160 compliance without added shielding. |
Use Scenario: Stabilizes reference voltage for ECG signal conditioning and isolation barrier drivers. IC Role / Device Role / Timing Role: Low-leakage (7 µA max) Zener reference ensuring baseline stability in microamp-level analog paths. Use Value: Tight ±5% tolerance and low temperature coefficient reduce calibration drift between patient measurements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4739A-TR | Same electrical specs and DO-41 axial package; lacks hermetic glass seal and high-temp rating | Suitable for commercial-grade PCBs where cost and board space are less constrained than reliability | Select when legacy through-hole assembly or lower-cost qualification is prioritized over 175°C operation |
| SMAJ4739A | Surface-mount SMA package; same 9.1 V/±5% spec but higher thermal resistance (150°C/W) and plastic body | Better suited for consumer electronics with ambient ≤85°C and no radiation or hermeticity requirements | Choose for high-volume automated assembly where JEDEC-standardized SMT footprint simplifies placement |
Compared with 1N4739A-TR and SMAJ4739A, the 1N4739UR-1/TR uniquely combines hermetic DO-213AB packaging, 175°C operation, and radiation hardness-making it the only option qualified for extended-life aerospace and downhole instrumentation where long-term parameter stability is non-negotiable.
Availability
1N4739UR-1/TR is available at Aetrix Electronics and suitable for switch-mode power supplies, industrial sensor references, aerospace power conditioning, and medical diagnostic equipment requiring stable component supply across extended temperature and reliability envelopes.
Supply support for 1N4739UR-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 (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability, radiation-hardened, and high-performance analog and mixed-signal components.
The 1N4739UR-1/TR belongs to Microsemi's surface-mount Zener diode product line designed specifically for applications demanding hermetic sealing, wide temperature operation, and long-term parametric stability in harsh environments.
FAQ
What is the Zener voltage tolerance for 1N4739UR-1/TR?
The 1N4739UR-1/TR has a nominal Zener voltage of 9.1 V with ±5% tolerance, indicated by the "A" suffix in its designation. This tolerance is verified at 28 mA test current and 30°C case temperature per the official Microsemi datasheet. The 1N4739UR-1/TR maintains this specification across its full operating temperature range from –65°C to +175°C.
Is 1N4739UR-1/TR RoHS compliant?
Yes, the 1N4739UR-1/TR carries the "e3" suffix, confirming RoHS compliance with lead-free matte-tin plating. It supports reflow soldering at 260°C for 10 seconds per JEDEC J-STD-020, and its termination meets MIL-STD-750 Method 2026 for solderability. The 1N4739UR-1/TR is fully compatible with lead-free manufacturing processes.
What package type does 1N4739UR-1/TR use?
The 1N4739UR-1/TR uses the DO-213AB glass MELF package - a hermetically sealed, leadless cylindrical surface-mount outline defined by JEDEC. Its dimensions are A = 2.39–2.66 mm (length), B = 4.80–5.20 mm (diameter), and C = 0.41–0.55 mm (band width). The cathode is marked by a single dark band on the glass body.
How does 1N4739UR-1/TR compare to 1N4739A in terms of thermal performance?
The 1N4739UR-1/TR has a junction-to-ambient thermal resistance of 130°C/W on FR4 with recommended footprint, while the axial 1N4739A (DO-41) typically exhibits ~100°C/W. Although the DO-41 may appear more conductive, the 1N4739UR-1/TR's hermetic glass construction allows safe operation up to 175°C - a capability the plastic-bodied 1N4739A cannot match.
Can 1N4739UR-1/TR be used in radiation-intensive environments?
Yes, the 1N4739UR-1/TR is inherently radiation-hardened per MicroNote 050 due to its hermetic glass MELF construction and silicon process. It is routinely screened to MIL-PRF-19500 standards (JAN/JANTXV/JANS) for total ionizing dose (TID) tolerance exceeding 100 krad(Si), making it suitable for satellite, nuclear, and high-altitude avionics applications where the 1N4739UR-1/TR's parametric stability under irradiation is critical.
1N4739UR-1/TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-213AB, MELF (Glass)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 9.1 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 5 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 7 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 175°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-213AB (MELF, LL41)
1N4739UR-1/TR FAQ
1.How can I place an order for 1N4739UR-1/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4739UR-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 1N4739UR-1/TR reliable?
The price and inventory of 1N4739UR-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 1N4739UR-1/TR is usually 5 days.
3.What payment methods are accepted for 1N4739UR-1/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4739UR-1/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4739UR-1/TR?
1N4739UR-1/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4739UR-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 1N4739UR-1/TR?
For technical support, including 1N4739UR-1/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4739UR-1/TR requirements.
6.How does Aetrix verify that 1N4739UR-1/TR is sourced from the original manufacturer or authorized distributors?
All 1N4739UR-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 1N4739UR-1/TR meets industry standards.
7.What is the process for return or replacement of 1N4739UR-1/TR?
All 1N4739UR-1/TR units undergo pre-shipment inspection (PSI). If there is an issue with 1N4739UR-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 1N4739UR-1/TR part is unused and in its original packaging.
Return procedure for 1N4739UR-1/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4739UR-1/TR Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
-
BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
Tech Hub
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
