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Microchip Technology 1N5349BE3/TR12
- Part No.:
- 1N5349BE3/TR12
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- T-18, Axial
- Datasheet:
-
1N5349BE3/TR12.pdf
- Description:
- DIODE ZENER 12V 5W T18
- Quantity:
- Payment:
- Shipping:
Inventory:3,652
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Product details
Overview
1N5349BE3/TR12 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 12 V, ±5% tolerance (B suffix), maximum dynamic impedance of 2.5 Ω at 100 mA test current, and maximum reverse current of 2.0 µA at 9.1 V. It operates from –65 °C to +150 °C and is used for precision voltage reference and overvoltage protection in industrial power supplies.
For engineers reviewing the 1N5349BE3/TR12 datasheet, 1N5349BE3/TR12 pinout, 1N5349BE3/TR12 application, or 1N5349BE3/TR12 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (25 °C/W junction-to-lead), surge current rating (7.5 A), voltage regulation (ΔVZ = 0.25 V), and RoHS-compliant matte-tin plating per MIL-STD-750.
Technical Context
This device functions as a two-terminal voltage regulator in reverse-biased mode, maintaining stable output across 10%–50% of its maximum Zener current (IZM = 100 mA). Its low dynamic impedance (2.5 Ω) ensures minimal voltage deviation under load transients.
Designed for through-hole mounting on FR4 PCBs or lead-soldered heat sinking, it delivers 5 W steady-state power at TL < 25 °C (3/8″ lead length), derating linearly above that temperature. The cathode band identifies polarity, and operation requires the banded end to be positive relative to the anode.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 12 V nominal, ±5% tolerance - defines regulated output level under specified test conditions (IZT = 100 mA). |
| Power Dissipation | 5.0 W at TL ≤ 25 °C - supports high-current regulation when adequately heat sunk via leads. |
| Dynamic Impedance (ZZ) | 2.5 Ω max at IZT = 100 mA - determines output voltage stability against current variation. |
| Reverse Current (IR) | 2.0 µA max at VR = 9.1 V - confirms low leakage in standby or low-power regulation modes. |
| Surge Current (IZSM) | 7.5 A peak (8.3 ms half-sine) - enables transient overvoltage clamping without failure. |
| Voltage Regulation (ΔVZ) | 0.25 V max - difference between VZ measured at 10% and 50% of IZM, indicating line regulation performance. |
| Thermal Resistance | 25 °C/W junction-to-lead (3/8″ lead length) - quantifies thermal path efficiency for lead-mounted heat dissipation. |
Pinout & Package
Package: Axial-leaded T-18 plastic case (void-free UL94V-0 epoxy), cathode indicated by colored band; leads are RoHS-compliant annealed matte-tin plated per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal in forward bias; referenced ground node in reverse-bias regulation | Connected to system ground or lower-potential rail; must be negative relative to cathode during regulation. |
| Cathode | Current exit terminal in forward bias; regulated output node in reverse bias | Banded end; connected to input supply rail; provides stable 12 V reference at defined current range. |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered Zener family | Ensures standardized electrical behavior and interchangeability across qualified suppliers. |
| Moisture sensitivity Level 1 | No dry pack required - simplifies handling and eliminates bake-out prior to assembly. |
| Nonsensitive to ESD (MIL-STD-750 Method 1020) | Enables safe manual handling and board-level integration without special ESD controls. |
| RoHS-compliant (e3 suffix) | Meets EU Directive 2011/65/EU - tin-lead-free plating compatible with lead-free reflow profiles. |
| Tape-and-reel packaging (TR12 suffix) | Supports automated SMT placement despite axial form factor - reduces manual loading in high-volume lines. |
Applications
| Industrial Power Supply Regulation | Overvoltage Protection Clamp |
|---|---|
|
Use Scenario: Stabilizing feedback reference in isolated DC-DC converter secondary-side error amplifiers. IC Role / Device Role / Timing Role: Zener diode providing precise 12 V reference to optocoupler input or TL431 shunt regulator. Use Value: Maintains ±0.6 V regulation window (±5%) across –40 °C to +85 °C ambient, enabling tight output voltage tolerance. |
Use Scenario: Clamping transient spikes on 12 V rail caused by relay coil flyback or inductive switching noise. IC Role / Device Role / Timing Role: Two-terminal shunt protector diverting surge energy to ground before downstream ICs exceed absolute maximum ratings. Use Value: Withstands 7.5 A non-recurrent surge (8.3 ms), limiting rail voltage to ≤12.25 V (VZ + ΔVZ) during fault events. |
| Programmable Logic Controller (PLC) Input Conditioning | Test Equipment Reference Source |
|
Use Scenario: Level-shifting and voltage limiting for 24 V digital inputs interfaced to 3.3 V or 5 V microcontrollers. IC Role / Device Role / Timing Role: Front-end Zener clamp protecting input protection diodes and internal ESD structures of logic ICs. Use Value: Low 2.5 Ω dynamic impedance minimizes voltage rise under fast-rising transients, preserving signal integrity at input sampling edges. |
Use Scenario: Providing stable 12 V reference in portable multimeter or calibration source front-end circuitry. IC Role / Device Role / Timing Role: Precision voltage standard for ADC reference scaling or DAC output buffering. Use Value: ΔVZ = 0.25 V ensures consistent 12 V output across 10–50 mA operating range, reducing measurement drift in battery-powered instruments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5349B | Same electrical specs but bulk-packaged (no TR12 tape-and-reel); identical T-18 package and RoHS compliance (e3 implied). | Not optimized for automated pick-and-place; suitable for hand-soldered prototypes or low-volume repair. | Select 1N5349B for bench validation or small-batch builds where reel feeding is unnecessary. |
| MMBZ5242B-TP | Surface-mount SOD-123 package; same 12 V/±5% rating but lower power (500 mW), higher ZZ (20 Ω), and IZM = 10 mA. | Intended for space-constrained PCBs with low-power biasing, not high-current regulation or surge clamping. | Choose MMBZ5242B-TP only when board area is critical and peak current remains below 10 mA. |
Compared with 1N5349B and MMBZ5242B-TP, the 1N5349BE3/TR12 uniquely combines 5 W power handling, axial-leaded mechanical robustness, tape-and-reel automation support, and verified 7.5 A surge capability - making it optimal for industrial-grade power conditioning where reliability and manufacturability intersect.
Availability
1N5349BE3/TR12 is available at Aetrix Electronics and suitable for industrial power supplies, overvoltage protection circuits, PLC input modules, and portable test equipment requiring stable component supply and long-term lifecycle continuity.
Supply support for 1N5349BE3/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 1N53xxB series was designed specifically for ruggedized voltage regulation in harsh-environment power systems, emphasizing thermal resilience, surge survivability, and JEDEC-standard consistency across military and commercial grades.
FAQ
What is the Zener voltage tolerance of the 1N5349BE3/TR12?
The 1N5349BE3/TR12 has a Zener voltage tolerance of ±5%, indicated by the "B" suffix in its part number. This means its actual regulation voltage falls between 11.4 V and 12.6 V when tested at 100 mA (IZT) and 25 °C lead temperature. The e3 suffix confirms RoHS compliance, and TR12 denotes tape-and-reel packaging - none of which affect the voltage tolerance specification of the 1N5349BE3/TR12.
Can the 1N5349BE3/TR12 be used in surface-mount designs?
No - the 1N5349BE3/TR12 uses an axial-leaded T-18 package intended for through-hole mounting. While it ships in tape-and-reel (TR12) format for automated handling, its physical form factor requires hole drilling and wave or selective soldering. For surface-mount equivalents, Microsemi offers the SMBJ5349B or SMBG5349B in DO-214AA/DO-214AB packages - neither shares pinout or footprint with the 1N5349BE3/TR12.
What is the maximum surge current rating for the 1N5349BE3/TR12?
The 1N5349BE3/TR12 is rated for a maximum non-recurrent surge current (IZSM) of 7.5 A, defined as the peak value of an 8.3 ms half-sine waveform. This rating assumes proper PCB layout with adequate copper pour and thermal relief. Exceeding this value, even briefly, risks irreversible junction damage - so the 1N5349BE3/TR12 must be applied within this limit in clamping applications.
How does the thermal resistance of the 1N5349BE3/TR12 affect its power handling?
The 1N5349BE3/TR12 has a junction-to-lead thermal resistance of 25 °C/W when mounted with 3/8″ (10 mm) lead length from the body. At ambient temperatures above 25 °C, its usable power must be derated linearly - e.g., at 75 °C lead temperature, maximum dissipation drops to 3.75 W. This directly limits continuous Zener current and must be calculated using actual board-level thermal conditions, not datasheet ambient-only values for the 1N5349BE3/TR12.
Is the 1N5349BE3/TR12 suitable for precision reference applications?
The 1N5349BE3/TR12 provides moderate precision: ±5% initial tolerance, 0.25 V voltage regulation (ΔVZ) across 10–50% of IZM, and 2.5 Ω dynamic impedance. It is appropriate for cost-sensitive industrial references but not metrology-grade systems. For higher accuracy, consider temperature-compensated references like the LM385 or TL431 - the 1N5349BE3/TR12 serves best where 12 V stabilization suffices without active compensation.
1N5349BE3/TR12 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- T-18, Axial
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 12 V
- Tolerance:
- ±5%
- Power - Max:
- 5 W
- Impedance (Max) (Zzt):
- 2.5 Ohms
- Current - Reverse Leakage @ Vr:
- 2 µA @ 8.6 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 1 A
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- T-18
1N5349BE3/TR12 FAQ
1.How can I place an order for 1N5349BE3/TR12 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5349BE3/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 1N5349BE3/TR12 reliable?
The price and inventory of 1N5349BE3/TR12 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5349BE3/TR12 is usually 5 days.
3.What payment methods are accepted for 1N5349BE3/TR12?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5349BE3/TR12 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5349BE3/TR12?
1N5349BE3/TR12 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5349BE3/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 1N5349BE3/TR12?
For technical support, including 1N5349BE3/TR12 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5349BE3/TR12 requirements.
6.How does Aetrix verify that 1N5349BE3/TR12 is sourced from the original manufacturer or authorized distributors?
All 1N5349BE3/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 1N5349BE3/TR12 meets industry standards.
7.What is the process for return or replacement of 1N5349BE3/TR12?
All 1N5349BE3/TR12 units undergo pre-shipment inspection (PSI). If there is an issue with 1N5349BE3/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 1N5349BE3/TR12 part is unused and in its original packaging.
Return procedure for 1N5349BE3/TR12:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5349BE3/TR12 Tags
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