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Microchip Technology 1N5343B/TR12
- Part No.:
- 1N5343B/TR12
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- T-18, Axial
- Datasheet:
-
1N5343B/TR12.pdf
- Description:
- DIODE ZENER 7.5V 5W T18
- Quantity:
- Payment:
- Shipping:
Inventory:4,838
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Product details
Overview
1N5343B/TR12 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 7.5 V ±5%, 175 mA test current, 1.5 Ω dynamic impedance at IZT, and maximum reverse current of 10 μA at 5.4 V. It operates from –65°C to +150°C and is used for precision voltage reference and overvoltage protection in power supply feedback loops.
For engineers reviewing the 1N5343B/TR12 datasheet, 1N5343B/TR12 pinout, 1N5343B/TR12 application, or 1N5343B/TR12 equivalent, key selection criteria include Zener voltage tolerance, thermal resistance (25 °C/W junction-to-lead), surge current rating (10.7 A), voltage regulation (ΔVZ = 0.15 V), and RoHS-compliant matte-tin plating per MIL-STD-750.
Technical Context
This discrete Zener diode functions as a two-terminal voltage regulator in shunt configuration, maintaining stable output voltage across wide operating current (175 mA IZT to 630 mA IZM) and temperature ranges. Its low dynamic impedance (1.5 Ω) ensures minimal voltage variation under load transients.
The device uses a void-free thermosetting epoxy T-18 package with cathode band marking, rated for 5.0 W steady-state dissipation at TL < 25°C (3/8" lead length), and exhibits 0.15 V voltage regulation between 10% and 50% of IZM - critical for high-stability reference designs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 7.5 V ±5% - defines regulated output voltage under 175 mA test current |
| Power Dissipation | 5.0 W at TL < 25°C - requires minimum 3/8" lead length for full rating |
| Dynamic Impedance (ZZ) | 1.5 Ω at IZT - ensures tight voltage control during current variations |
| Max Reverse Current (IR) | 10 μA at VR = 5.4 V - guarantees low leakage below regulation threshold |
| Surge Current (IZSM) | 10.7 A (8.3 ms half-sine) - supports transient overvoltage clamping |
| Voltage Regulation (ΔVZ) | 0.15 V - difference between voltages at 10% and 50% of IZM |
| Junction-to-Lead Rθ | 25 °C/W - enables thermal design with simple lead heatsinking |
Pinout & Package
Package: T-18 axial-leaded plastic encapsulated case per JEDEC DO-204AL, void-free UL94V-0 epoxy body, cathode indicated by colored band, 0.7 g weight, RoHS-compliant matte-tin plating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal in forward bias; referenced to cathode in Zener operation | Connected to lower-potential node (e.g., ground or return path) when regulating |
| Cathode | Current exit terminal in forward bias; Zener voltage reference terminal | Banded end - connected to higher-potential node (e.g., supply rail) to clamp voltage |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered Zener | Complies with industry-standard DO-204AL mechanical and electrical definitions |
| Moisture Sensitivity Level 1 | No dry pack required - simplifies handling and eliminates bake-out prior to assembly |
| Nonsensitive to ESD | Qualified per MIL-STD-750 Method 1020 - no special ESD controls needed in manufacturing |
| High surge current capability | 10.7 A peak (8.3 ms) - provides robust transient suppression without external components |
| Stable voltage regulation | ΔVZ = 0.15 V across 10–50% IZM - reduces need for post-regulation filtering |
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: Shunt voltage reference providing precise 7.5 V setpoint for optocoupler-driven control loop. Use Value: Low ΔVZ (0.15 V) and 1.5 Ω ZZ maintain tight output regulation (<±1%) across line/load variations. | Use Scenario: Supplies stable excitation voltage to bridge-based pressure transducers in factory automation systems. IC Role / Device Role / Timing Role: Precision analog reference source replacing higher-cost IC references where 7.5 V suffices. Use Value: ±5% tolerance and 10 μA IR at 5.4 V ensure repeatable sensor offset calibration over –40°C to +85°C ambient. |
| Overvoltage Clamp for MCU I/O | Programmable Threshold Detector |
Use Scenario: Protects 3.3 V or 5 V microcontroller GPIO pins against ESD and inductive kickback. IC Role / Device Role / Timing Role: Bidirectional transient suppressor configured with series resistor to limit current into 1N5343B/TR12 cathode. Use Value: 10.7 A surge rating and 25 °C/W thermal resistance enable single-device clamping without thermal runaway. | Use Scenario: Sets trip point for comparator-based battery undervoltage lockout in portable medical devices. IC Role / Device Role / Timing Role: Stable 7.5 V reference feeding non-inverting input of rail-to-rail comparator. Use Value: Tight 1.5 Ω ZZ minimizes hysteresis error; 0.7 g weight supports compact PCB layout in space-constrained enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5343B (bulk) | Identical electrical specs; differs only in packaging - no tape-and-reel (TR12) carrier | Not suitable for automated pick-and-place; requires manual or bulk-feed placement | Select 1N5343B/TR12 for SMT production lines requiring EIA-296 compliant tape-and-reel delivery |
| MMSZ5235B-TP (Micro Commercial) | Surface-mount SOD-123 package; 7.5 V ±5%, but lower 500 mW rating and 30 Ω ZZ | Limited to low-power signal-level regulation; cannot replace 1N5343B/TR12 in 5 W power stages | Choose MMSZ5235B-TP only for space-constrained, low-current biasing where thermal mass is not required |
Compared with 1N5343B/TR12, the bulk 1N5343B offers identical performance but lacks tape-and-reel convenience, while MMSZ5235B-TP trades power handling and impedance for miniaturization - making 1N5343B/TR12 optimal for mid-power industrial regulation where reliability and thermal margin are prioritized.
Availability
1N5343B/TR12 is available at Aetrix Electronics and suitable for switch-mode power supplies, industrial sensor references, overvoltage clamps, and programmable threshold detectors requiring stable component supply and JEDEC-standard compliance.
Supply support for 1N5343B/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, RF, and timing solutions for aerospace, defense, and industrial markets.
The 1N53xxB series was designed for ruggedized, high-stability voltage regulation in harsh-environment power systems - emphasizing thermal robustness, surge resilience, and long-term parametric consistency.
FAQ
What is the Zener voltage tolerance of the 1N5343B/TR12?
The 1N5343B/TR12 has a Zener voltage tolerance of ±5%, as indicated by the "B" suffix in its part number. This means its nominal 7.5 V regulation voltage falls within 7.125 V to 7.875 V at 25°C under 175 mA test current, per Microsemi's REV D datasheet.
Can the 1N5343B/TR12 be used in surface-mount designs?
No - the 1N5343B/TR12 uses an axial-leaded T-18 (DO-204AL) package and is not a surface-mount device. For SMT equivalents, Microsemi offers the SMBJ5343B or SMBG5343B series; the 1N5343B/TR12 requires through-hole mounting with 3/8" lead length for full 5 W rating.
What is the maximum surge current rating for the 1N5343B/TR12?
The 1N5343B/TR12 is rated for a maximum non-recurrent surge current (IZSM) of 10.7 A, defined as the peak of an 8.3 ms half-sine waveform. This value is specified in the "ELECTRICAL CHARACTERISTICS" table on page 1 of the Microsemi datasheet and supports transient overvoltage suppression in power rails.
Does the 1N5343B/TR12 require moisture preconditioning before reflow?
No - the 1N5343B/TR12 has IPC/JEDEC J-STD-020B Moisture Sensitivity Level 1, meaning it is not moisture-sensitive and requires no dry pack or baking prior to soldering. Its void-free epoxy encapsulation eliminates moisture ingress risk during standard reflow profiles up to 260°C for 10 seconds.
How does thermal resistance affect the 1N5343B/TR12's power rating?
The 1N5343B/TR12 has a junction-to-lead thermal resistance of 25 °C/W when leads are trimmed to 3/8" (10 mm) from the body. This allows full 5.0 W dissipation at TL < 25°C; derating is required above that temperature per Figure 1 in the datasheet - e.g., ~3.5 W at TL = 50°C.
1N5343B/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):
- 7.5 V
- Tolerance:
- ±5%
- Power - Max:
- 5 W
- Impedance (Max) (Zzt):
- 1.5 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 5.4 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
1N5343B/TR12 FAQ
1.How can I place an order for 1N5343B/TR12 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5343B/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 1N5343B/TR12 reliable?
The price and inventory of 1N5343B/TR12 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5343B/TR12 is usually 5 days.
3.What payment methods are accepted for 1N5343B/TR12?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5343B/TR12 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5343B/TR12?
1N5343B/TR12 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5343B/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 1N5343B/TR12?
For technical support, including 1N5343B/TR12 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5343B/TR12 requirements.
6.How does Aetrix verify that 1N5343B/TR12 is sourced from the original manufacturer or authorized distributors?
All 1N5343B/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 1N5343B/TR12 meets industry standards.
7.What is the process for return or replacement of 1N5343B/TR12?
All 1N5343B/TR12 units undergo pre-shipment inspection (PSI). If there is an issue with 1N5343B/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 1N5343B/TR12 part is unused and in its original packaging.
Return procedure for 1N5343B/TR12:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5343B/TR12 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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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
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SMAZ12-13-F
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