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Microchip Technology 1N4746PE3/TR12
- Part No.:
- 1N4746PE3/TR12
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4746PE3/TR12.pdf
- Description:
- DIODE ZENER 18V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:9,267
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Product details
Overview
1N4746PE3/TR12 from Microsemi is a 1 W, 18 V ±5% Zener diode in DO-41 plastic package, rated for 14 mA test current, 20 Ω dynamic impedance at IZT, and 5 µA reverse leakage at 13.7 V, used for precision voltage regulation in power supply feedback loops and reference circuits.
For engineers reviewing the 1N4746PE3/TR12 datasheet, 1N4746PE3/TR12 pinout, 1N4746PE3/TR12 application, or 1N4746PE3/TR12 equivalent, key selection criteria include Zener voltage tolerance, thermal resistance (45 °C/W junction-to-lead), surge current rating (250 mA), RoHS compliance (e3 suffix), and tape-and-reel packaging (TR12).
Technical Context
This device operates in reverse breakdown to maintain stable 18 V output across 0.25–250 mA regulation current range, with temperature coefficient near zero (±2 mV/°C) due to its 18 V nominal Zener voltage. It exhibits sharp knee characteristics verified by dual-point Zener impedance measurement per JEDEC standards.
Designed for axial-leaded mounting on FR4 PCBs with 1 oz copper, it delivers 1.0 W steady-state dissipation at TL < 105 °C (3/8″ lead length) or TA < 45 °C, and supports soldering at 260 °C for 10 s without degradation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 18 V ±5% at 14 mA - defines regulated output level with tight tolerance for feedback accuracy |
| Power Dissipation | 1.0 W at 25 °C - sets maximum continuous thermal load before derating begins |
| Dynamic Impedance (ZZT) | 20 Ω at 14 mA - determines output voltage variation under load transients |
| Reverse Leakage Current | 5 µA max at 13.7 V - ensures minimal quiescent power loss below regulation threshold |
| Surge Current (ISM) | 250 mA - supports short-duration overvoltage events without failure |
| Thermal Resistance | 45 °C/W junction-to-lead - enables thermal design using lead length as heatsink path |
| Operating Temperature | −65 °C to +150 °C - suitable for industrial and automotive under-hood environments |
Pinout & Package
DO-41 (DO-204AL) plastic axial-leaded package with cathode indicated by band; terminals are anode and cathode only - no internal circuitry or multi-pin configuration.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference | Connected to lower-potential node; reverse-biased operation requires cathode at higher potential |
| Cathode (banded end) | Zener regulation terminal | Applied positive bias relative to anode to enter breakdown; carries full regulation current |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC 1N47xxA-compliant construction | Ensures mechanical and electrical interchangeability with legacy 1W Zener designs |
| RoHS-compliant matte-tin plating (e3) | Enables lead-free assembly without solderability compromise or whisker risk |
| Moisture sensitivity Level 1 | Eliminates dry-pack requirement and floor-life constraints for SMT handling |
| Tape-and-reel packaging (TR12) | Supports automated pick-and-place insertion at standard industry reel quantities |
| Nonsensitive to ESD (MIL-STD-750 Method 1020) | Reduces need for special ESD handling during board assembly and test |
Applications
| Switch-Mode Power Supply Feedback | Industrial Sensor Reference |
|---|---|
Use Scenario: Regulates error amplifier input in isolated flyback converter feedback network. IC Role / Device Role / Timing Role: Zener diode providing precise 18 V reference to optocoupler LED drive circuit. Use Value: Maintains ±1% output voltage accuracy across line/load/temperature with 20 Ω ZZT limiting feedback loop perturbation. | Use Scenario: Stabilizes excitation voltage for bridge-based pressure transducers in factory automation. IC Role / Device Role / Timing Role: Voltage reference source for ratiometric analog signal conditioning. Use Value: Delivers stable 18 V with <±2 mV/°C TC over −40 °C to +85 °C, minimizing sensor offset drift. |
| Overvoltage Clamp Protection | Programmable Threshold Detector |
Use Scenario: Clamps transient spikes on 15 V rail in motor drive control logic. IC Role / Device Role / Timing Role: Shunt protection element diverting surge current above 13.7 V threshold. Use Value: Absorbs 250 mA surge pulses without degradation, leveraging 1 W power rating and robust DO-41 package. | Use Scenario: Sets trip point for comparator monitoring battery pack voltage in portable medical devices. IC Role / Device Role / Timing Role: Precision threshold element defining 18 V undervoltage lockout (UVLO) boundary. Use Value: Enables accurate UVLO activation with 5% VZ tolerance and low 5 µA leakage preserving standby current budget. |
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 package | Not suitable for lead-free assembly; requires Pb-based solder process | Select when legacy Pb-process compatibility is required and RoHS exemption applies |
| MMSZ4708T1G | Surface-mount SOD-123 package; 18 V ±5%; 500 mW rating; 30 Ω ZZT; different thermal profile | Lower power and smaller footprint; not drop-in replaceable due to package and thermal limits | Select for space-constrained PCBs where 500 mW regulation suffices and reflow compatibility is needed |
Compared with 1N4746A and MMSZ4708T1G, the 1N4746PE3/TR12 offers full 1 W dissipation in through-hole DO-41 with RoHS-compliant terminations and tape-and-reel delivery-making it optimal for high-reliability industrial power supplies requiring proven thermal margin and assembly flexibility.
Availability
1N4746PE3/TR12 is available at Aetrix Electronics and suitable for industrial power supplies, sensor signal conditioning, overvoltage protection circuits, and programmable threshold detection requiring stable component supply and long-term obsolescence management.
Supply support for 1N4746PE3/TR12 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 and mixed-signal components for aerospace, defense, and industrial markets.
The 1N47xxAP series was engineered for ruggedized voltage regulation in mission-critical power systems, emphasizing thermal stability, moisture resilience, and JEDEC-standard interoperability.
FAQ
What is the Zener voltage tolerance of the 1N4746PE3/TR12?
The 1N4746PE3/TR12 has a Zener voltage tolerance of ±5%, confirmed by the "A" suffix in its JEDEC designation and specified in Microsemi's official datasheet revision C (2005). This means its measured VZ falls between 17.1 V and 18.9 V at 14 mA test current and 25 °C lead temperature. The tolerance directly impacts regulation accuracy in feedback and reference applications.
Does the 1N4746PE3/TR12 support lead-free soldering processes?
Yes, the 1N4746PE3/TR12 supports lead-free soldering: its "e3" suffix denotes RoHS-compliant annealed matte-tin plating, qualified for 260 °C for 10 seconds per MIL-STD-750 Method 2026. This ensures reliable wetting and joint integrity in Pb-free reflow profiles without compromising termination adhesion or corrosion resistance.
What is the maximum steady-state power dissipation for the 1N4746PE3/TR12?
The 1N4746PE3/TR12 is rated for 1.0 W steady-state power dissipation at TL < 105 °C (measured 3/8″ from body) or TA < 45 °C on FR4 with specified copper layout. Derating is required above these temperatures per Figure 1 in the datasheet, reaching zero watt capability at 150 °C ambient or 175 °C lead temperature.
How is polarity marked on the 1N4746PE3/TR12?
The 1N4746PE3/TR12 uses a cathode band painted on the body to indicate polarity: the banded end is the cathode and must be held at a higher potential than the anode to achieve Zener regulation. Forward voltage is ≤1.2 V at 200 mA, confirming standard silicon diode behavior in forward bias.
What does the "TR12" suffix indicate in 1N4746PE3/TR12?
The "TR12" suffix indicates tape-and-reel packaging per EIA-296 standard, with 12,000 units per reel. This format enables automated surface-mount and through-hole placement equipment compatibility, reduces handling damage, and supports just-in-time manufacturing workflows for high-volume production of the 1N4746PE3/TR12.
1N4746PE3/TR12 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)
1N4746PE3/TR12 FAQ
1.How can I place an order for 1N4746PE3/TR12 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4746PE3/TR12 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 1N4746PE3/TR12 reliable?
The price and inventory of 1N4746PE3/TR12 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4746PE3/TR12 is usually 5 days.
3.What payment methods are accepted for 1N4746PE3/TR12?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4746PE3/TR12 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4746PE3/TR12?
1N4746PE3/TR12 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4746PE3/TR12 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 1N4746PE3/TR12?
For technical support, including 1N4746PE3/TR12 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4746PE3/TR12 requirements.
6.How does Aetrix verify that 1N4746PE3/TR12 is sourced from the original manufacturer or authorized distributors?
All 1N4746PE3/TR12 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 1N4746PE3/TR12 meets industry standards.
7.What is the process for return or replacement of 1N4746PE3/TR12?
All 1N4746PE3/TR12 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4746PE3/TR12, 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 1N4746PE3/TR12 part is unused and in its original packaging.
Return procedure for 1N4746PE3/TR12:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4746PE3/TR12 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
Diodes Incorporated
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SMAZ12-13-F
Diodes Incorporated
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