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Microchip Technology 1N4737UR/TR
- Part No.:
- 1N4737UR/TR
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-213AB, MELF (Glass)
- Datasheet:
-
1N4737UR/TR.pdf
- Description:
- DIODE ZENER 7.5V 1W DO213AB
- Quantity:
- Payment:
- Shipping:
Inventory:9,637
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Product details
Overview
1N4737UR/TR from Microsemi is a surface-mount 1.0 W glass-encapsulated Zener diode with a nominal Zener voltage of 7.5 V ±5%, 4.0 mA test current, 4.0 Ω dynamic impedance at IZT, and maximum reverse leakage of 5 µA at 6.0 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 1N4737UR/TR datasheet, 1N4737UR/TR pinout, 1N4737UR/TR application, or 1N4737UR/TR equivalent, key selection criteria include its DO-213AB MELF glass package, hermetic sealing, radiation hardness per MicroNote 050, low parasitic capacitance, and RoHS-compliant e3 termination.
Technical Context
This device functions as a two-terminal voltage reference diode operating in reverse breakdown. Its Zener voltage is specified at 30 °C with 90-second stabilization time, and it maintains regulation across a broad current range (IZK = 0.5 mA to IZM = 121 mA at TA = 50 °C) and temperature extremes (−65 °C to +175 °C).
The DO-213AB glass MELF package provides hermeticity, ESD insensitivity, and low thermal resistance (50 °C/W junction-to-end-cap). Its leadless construction supports high-density PCB layouts while delivering stable regulation without solder joint fatigue concerns typical of axial leads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 7.5 V ±5% - precise regulation point for feedback networks requiring tight tolerance without external trimming |
| Power Dissipation | 1.0 W at TEC < 125 °C - enables compact thermal design with end-cap heatsinking on metal-core or thick-copper boards |
| Dynamic Impedance (ZZT) | 4.0 Ω @ 4.0 mA - ensures minimal output voltage variation under load transients in closed-loop regulators |
| Reverse Leakage Current | 5 µA @ 6.0 V - guarantees low quiescent error contribution in high-impedance reference paths |
| Operating Temperature | −65 °C to +175 °C - supports deployment in aerospace, downhole, and industrial environments without derating penalties |
| Forward Voltage | 1.2 V max @ 200 mA - allows safe forward-bias clamping during transient overvoltage events |
| Thermal Resistance | 50 °C/W junction-to-end-cap - permits direct thermal coupling to copper pour or chassis for sustained 1 W operation |
Pinout & Package
Package: DO-213AB glass MELF (hermetically sealed, leadless cylindrical body, cathode band marking). Dimensions: A = 2.39–2.66 mm (diameter), B = 4.80–5.20 mm (length), C = 0.41–0.55 mm (band width). Cathode indicated by single black band; device operated with banded end positive for Zener regulation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Reference ground node | Connected to system ground or feedback divider low-side; defines 0 V reference for regulation loop |
| Cathode | Zener regulation node | Connected to regulated rail or error amplifier input; supplies stable 7.5 V reference under reverse bias |
Key Features
| Feature | Design Value |
|---|---|
| Hermetic glass MELF construction | Eliminates moisture ingress and long-term parameter drift in humid or corrosive environments |
| Radiation hardness (MicroNote 050) | Enables use in space-grade and nuclear instrumentation without additional shielding or qualification |
| Nonsensitive to ESD | Withstands human-body-model discharges >15 kV without parameter shift-reduces handling controls in production |
| RoHS-compliant e3 termination | Tin-plated terminals compatible with lead-free reflow profiles up to 260 °C for 10 s |
| Stable 1%–5% voltage tolerance options | Supports cost-optimized designs (±5%) or high-precision references (±1% with D suffix) without redesign |
Applications
| Industrial Power Supplies | Avionics Reference Circuits |
|---|---|
Use Scenario: Feedback voltage sensing in isolated DC/DC converters for programmable logic controllers. IC Role / Device Role / Timing Role: Zener diode providing 7.5 V reference to optocoupler input or TL431 shunt regulator. Use Value: Stable regulation over −40 °C to +85 °C ambient ensures consistent output accuracy without calibration drift. |
Use Scenario: Precision voltage reference for analog-to-digital conversion in flight control sensor interfaces. IC Role / Device Role / Timing Role: Two-terminal reference source feeding ADC reference buffer or op-amp gain-setting network. Use Value: Hermetic glass package prevents parameter shift during thermal cycling and altitude-induced pressure changes. |
| Downhole Oilfield Electronics | Medical Imaging Power Management |
Use Scenario: Voltage clamping and regulation in high-temperature motor drive gate drivers deployed at 150 °C wellbore conditions. IC Role / Device Role / Timing Role: Zener clamp protecting gate driver inputs from transient overvoltage during switching events. Use Value: Continuous operation at +175 °C junction temperature eliminates need for active cooling or derating. |
Use Scenario: Bias voltage generation for photomultiplier tube (PMT) high-voltage supplies in PET scanners. IC Role / Device Role / Timing Role: Stable 7.5 V reference setting current limit thresholds and DAC offsets in HV control loops. Use Value: Low 5 µA leakage at 6.0 V minimizes error injection into ultra-low-current feedback paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4737AUR | Same Zener voltage (7.5 V), same DO-213AB package, but supplied in bulk-not tape-and-reel; no "TR" suffix | Lacks standardized reel packaging for automated SMT placement; requires manual loading or tube-to-tape conversion | Select 1N4737UR/TR when full SMT line compatibility and traceable lot-controlled reels are required |
| SMAJ4737A | Plastic-packaged SMA surface-mount variant; same 7.5 V rating but higher ZZT (7 Ω), wider tolerance (±5%), and lower max temp (150 °C) | Not hermetically sealed; unsuitable for high-reliability, radiation-hardened, or extended-temperature deployments | Choose SMAJ4737A only for cost-sensitive commercial applications where glass MELF robustness is not mandated |
Compared with 1N4737AUR and SMAJ4737A, the 1N4737UR/TR uniquely combines tape-and-reel delivery, hermetic glass construction, radiation hardness, and full −65 °C to +175 °C operation-making it the sole option for mission-critical, high-temperature, or space-qualified voltage reference roles.
Availability
1N4737UR/TR is available at Aetrix Electronics and suitable for industrial power supplies, avionics reference circuits, and downhole electronics requiring stable component supply, long-lifecycle availability, and guaranteed RoHS compliance.
Supply support for 1N4737UR/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-temperature analog and mixed-signal components.
The 1N4737UR/TR belongs to Microsemi's legacy surface-mount Zener diode family designed for voltage regulation in harsh-environment systems where hermeticity, thermal stability, and long-term parametric consistency are mandatory.
FAQ
What is the Zener voltage tolerance for 1N4737UR/TR?
The 1N4737UR/TR has a nominal Zener voltage of 7.5 V with a tolerance of ±5%, as indicated by the "A" suffix in its full designation. This tolerance is verified at 30 °C with 90-second stabilization after current application, per Microsemi's electrical characteristics table on page 2 of the datasheet.
Does 1N4737UR/TR require special handling for ESD sensitivity?
No-1N4737UR/TR is explicitly characterized as nonsensitive to ESD in its official documentation. It withstands high-energy discharges without parameter shift, eliminating the need for ESD-safe workstations or wrist straps during standard assembly, unlike many silicon-based discrete devices.
Can 1N4737UR/TR be used in reflow soldering processes?
Yes-1N4737UR/TR features RoHS-compliant e3 matte-tin plating and is rated for solder temperatures up to 260 °C for 10 seconds, fully compatible with industry-standard lead-free reflow profiles including IPC-J-STD-020 requirements.
What is the maximum steady-state power dissipation for 1N4737UR/TR at 70°C ambient?
At 70 °C ambient on an FR4 board with 1 oz copper and recommended footprint, the 1N4737UR/TR derates to approximately 0.75 W, based on its 130 °C/W junction-to-ambient thermal resistance and Figure 1 derating curve. Full 1.0 W operation requires end-cap heatsinking or lower ambient temperatures.
Is 1N4737UR/TR suitable for aerospace applications requiring radiation hardness?
Yes-the 1N4737UR/TR is inherently radiation-hardened per MicroNote 050, a documented qualification supporting use in low-earth orbit and other radiation-exposed environments without additional testing or screening, distinguishing it from commercial-grade Zeners.
1N4737UR/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):
- 7.5 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 4 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 5 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)
1N4737UR/TR FAQ
1.How can I place an order for 1N4737UR/TR through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4737UR/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 1N4737UR/TR reliable?
The price and inventory of 1N4737UR/TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4737UR/TR is usually 5 days.
3.What payment methods are accepted for 1N4737UR/TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4737UR/TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4737UR/TR?
1N4737UR/TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4737UR/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 1N4737UR/TR?
For technical support, including 1N4737UR/TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4737UR/TR requirements.
6.How does Aetrix verify that 1N4737UR/TR is sourced from the original manufacturer or authorized distributors?
All 1N4737UR/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 1N4737UR/TR meets industry standards.
7.What is the process for return or replacement of 1N4737UR/TR?
All 1N4737UR/TR units undergo pre-shipment inspection (PSI). If there is an issue with 1N4737UR/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 1N4737UR/TR part is unused and in its original packaging.
Return procedure for 1N4737UR/TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4737UR/TR Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
-
MMSZ5231B-7-F
Diodes Incorporated
-
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
-
MM5Z5V1ST1G
onsemi
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SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
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