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Microchip Technology 1N4746E3/TR13
- Part No.:
- 1N4746E3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4746E3/TR13.pdf
- Description:
- DIODE ZENER 18V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:4,947
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Product details
Overview
1N4746E3/TR13 from Microsemi is a 1 W, 18 V ±5% Zener diode in DO-41 plastic package, rated for 14 mA test current (IZT), 20 Ω dynamic impedance (ZZT), and 0.25 mA maximum reverse leakage at 13.7 V (VR). It delivers stable voltage regulation in power supply reference, overvoltage protection, and biasing circuits across -65°C to +150°C.
For engineers reviewing the 1N4746E3/TR13 datasheet, 1N4746E3/TR13 pinout, 1N4746E3/TR13 application, or 1N4746E3/TR13 equivalent, key selection criteria include its 18 V nominal Zener voltage, 1 W steady-state power rating at TL < 105°C, 45 °C/W junction-to-lead thermal resistance, RoHS-compliant matte-tin plating, and tape-and-reel packaging (TR13).
Technical Context
This discrete Zener diode operates in reverse breakdown to maintain a stable 18 V reference across a wide regulation current range (0.25 mA to 250 mA), with sharp knee characteristics verified by dual-point Zener impedance measurement per MicroNote 202. Its DO-41 axial-leaded plastic package provides Level 1 moisture sensitivity (J-STD-020B) and eliminates dry-pack requirements.
The device exhibits a typical temperature coefficient near +0.075 %/°C (≈ +13.5 mV/°C) for 18 V Zeners per Figure 3, and supports soldering at 260°C for 10 s. Forward voltage is ≤1.2 V at 200 mA, and polarity is marked by cathode band - operation requires cathode-positive bias for regulation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 18 V ±5% at IZT = 14 mA - defines primary regulation setpoint under standard test conditions |
| Power Dissipation | 1.0 W at TL < 105°C (3/8″ lead length) - sets maximum continuous thermal load on PCB layout |
| Dynamic Impedance (ZZT) | 20 Ω at IZT = 14 mA - determines output voltage variation under changing load current |
| Reverse Leakage (IR) | 0.25 μA max at VR = 13.7 V - ensures minimal quiescent current in high-impedance bias networks |
| Thermal Resistance | 45 °C/W junction-to-lead - enables thermal design using lead conduction, not ambient convection |
| Operating Temperature | -65°C to +150°C - supports industrial, automotive under-hood, and military-grade environments |
| Package | DO-41 (DO-204AL) plastic - axial-leaded, UL94V-0 epoxy body, cathode band marking |
Pinout & Package
1N4746E3/TR13 uses a two-terminal DO-41 (DO-204AL) axial-leaded plastic package. Polarity is indicated by a cathode band; the banded end is the cathode (K), and the unmarked end is the anode (A). No PCB footprint changes are required when replacing legacy 1N47xxA series Zeners in existing through-hole designs.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (A) | Forward conduction terminal / Zener cathode reference | Connected to lower-potential node; reverse-biased during regulation |
| Cathode (K) | Zener breakdown terminal / regulation output | Banded end; connected to higher-potential node to enable reverse breakdown at 18 V |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered 1N47xxA series | Industry-standard footprint and electrical behavior - ensures compatibility with legacy designs and reference schematics |
| RoHS-compliant "e3" suffix | Matte-tin plating per MIL-STD-750 Method 2026 - eliminates lead while maintaining solderability and reliability |
| Tape-and-reel packaging ("TR13") | EIA-296 compliant 13-inch reel - supports automated SMT-compatible through-hole insertion and inventory traceability |
| Level 1 moisture sensitivity | No dry pack required per IPC/JEDEC J-STD-020B - reduces handling cost and simplifies storage logistics |
| Nonsensitive to ESD | Qualified per MIL-STD-750 Method 1020 - withstands handling without special grounding protocols |
Applications
| Power Supply Reference | Overvoltage Protection Clamp |
|---|---|
Use Scenario: Stabilizing feedback voltage in linear regulator ICs or op-amp-based shunt regulators. IC Role / Device Role / Timing Role: Voltage reference element providing precise 18 V setpoint for error amplifier comparison. Use Value: Maintains ±5% output accuracy over 0.25–250 mA load range and -65°C to +150°C ambient, reducing need for trimming. |
Use Scenario: Clamping transient surges on 15 V logic rails or sensor inputs exposed to ESD or inductive kickback. IC Role / Device Role / Timing Role: Shunt protection device that conducts above 18 V to limit downstream voltage excursion. Use Value: Absorbs up to 250 mA surge current (ISM) without degradation, protecting 3.3/5/12 V interface ICs. |
| Bias Network Stabilizer | Temperature-Compensated Reference |
Use Scenario: Setting fixed bias points for BJT amplifiers or MOSFET gate drivers requiring stable DC offset. IC Role / Device Role / Timing Role: Passive voltage source establishing repeatable operating point independent of supply ripple. Use Value: Delivers low dynamic impedance (20 Ω) to suppress noise coupling into sensitive analog nodes. |
Use Scenario: Paired with complementary-tempco components (e.g., forward-biased diodes) to build zero-drift references. IC Role / Device Role / Timing Role: Primary Zener element whose +13.5 mV/°C tempco is actively canceled in composite circuits. Use Value: Predictable, documented temperature coefficient enables precision compensation in instrumentation-grade references. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4746A | No "e3" RoHS suffix; Sn/Pb terminations; same VZ, IZT, ZZT, and DO-41 package | Not suitable for lead-free assembly; otherwise identical functional behavior in non-RoHS designs | Select 1N4746A only for legacy Sn/Pb reflow processes where RoHS compliance is not required |
| MMSZ4708T1G | Surface-mount SOD-123 package; 18 V ±5%; 500 mW rating; 30 Ω ZZT at 5 mA | Lower power and higher impedance limit use to low-current biasing; requires PCB redesign | Choose MMSZ4708T1G only when space-constrained layouts demand SMT and 500 mW suffices |
Compared with 1N4746A and MMSZ4708T1G, the 1N4746E3/TR13 uniquely combines full 1 W dissipation, DO-41 through-hole compatibility, RoHS compliance, and tape-and-reel automation support - making it optimal for industrial power supplies requiring long-term component continuity and mixed-technology assembly.
Availability
1N4746E3/TR13 is available at Aetrix Electronics and suitable for power supply reference, overvoltage clamp, and analog bias network applications requiring stable component supply, long-lifecycle availability, and RoHS-compliant manufacturing.
Supply support for 1N4746E3/TR13 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, RF, and timing solutions for aerospace, defense, and industrial markets.
The 1N47xxA Zener series was designed for robust, standardized voltage regulation in mission-critical power and protection circuits - emphasizing JEDEC registration, extended temperature operation, and screening-ready variants.
FAQ
What is the Zener voltage tolerance of the 1N4746E3/TR13?
The 1N4746E3/TR13 has a nominal Zener voltage of 18 V with a tolerance of ±5%, as indicated by the "A" suffix in its base part number (1N4746A). This tolerance is measured at 14 mA test current and 25°C lead temperature, and applies across the full operating temperature range per JEDEC specification.
Does the 1N4746E3/TR13 require dry packing before PCB assembly?
No, the 1N4746E3/TR13 is moisture sensitivity level (MSL) 1 per IPC/JEDEC J-STD-020B, meaning it does not require dry packing or baking prior to assembly. Its void-free thermosetting epoxy body inherently resists moisture absorption, simplifying storage and handling logistics.
What is the maximum surge current rating for the 1N4746E3/TR13?
The 1N4746E3/TR13 has a maximum non-repetitive surge current (ISM) of 250 mA, measured using a ½-sine wave pulse of 1/120 second duration at 25°C ambient. This rating enables reliable clamping of short-duration transients in power rail protection circuits.
Can the 1N4746E3/TR13 be used in surface-mount designs?
No - the 1N4746E3/TR13 is packaged in the axial-leaded DO-41 (DO-204AL) through-hole format and is not compatible with SMT placement. For surface-mount equivalents, consider the SMAJ4746A or MLL4746A series, which share the same 18 V Zener voltage but use SMC or Mini-MELF packages.
What does the "TR13" suffix indicate in 1N4746E3/TR13?
The "TR13" suffix indicates EIA-296 compliant tape-and-reel packaging on a 13-inch reel. This configuration supports automated pick-and-place insertion for through-hole components and enables traceable lot control, inventory management, and consistent feed performance in high-volume production lines.
1N4746E3/TR13 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-204AL, DO-41, Axial
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 18 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 20 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 13.7 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AL (DO-41)
1N4746E3/TR13 FAQ
1.How can I place an order for 1N4746E3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4746E3/TR13 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 1N4746E3/TR13 reliable?
The price and inventory of 1N4746E3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4746E3/TR13 is usually 5 days.
3.What payment methods are accepted for 1N4746E3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4746E3/TR13 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4746E3/TR13?
1N4746E3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4746E3/TR13 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 1N4746E3/TR13?
For technical support, including 1N4746E3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4746E3/TR13 requirements.
6.How does Aetrix verify that 1N4746E3/TR13 is sourced from the original manufacturer or authorized distributors?
All 1N4746E3/TR13 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 1N4746E3/TR13 meets industry standards.
7.What is the process for return or replacement of 1N4746E3/TR13?
All 1N4746E3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4746E3/TR13, 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 1N4746E3/TR13 part is unused and in its original packaging.
Return procedure for 1N4746E3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4746E3/TR13 Tags
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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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BZX84C3V3LT1G
onsemi
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MMSZ5245BS-7-F
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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
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