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Microchip Technology 1N5373B/TR8
- Part No.:
- 1N5373B/TR8
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- T-18, Axial
- Datasheet:
-
1N5373B/TR8.pdf
- Description:
- DIODE ZENER 68V 5W T18
- Quantity:
- Payment:
- Shipping:
Inventory:4,936
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Product details
Overview
1N5373B/TR8 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 68 V, ±5% tolerance (B suffix), 20 mA test current (IZT), 44 Ω maximum dynamic impedance (ZZ), and 0.5 μA maximum reverse leakage at 51.7 V (VR). 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 1N5373B/TR8 datasheet, 1N5373B/TR8 pinout, 1N5373B/TR8 application, or 1N5373B/TR8 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (25 °C/W junction-to-lead), surge current rating (500 A), voltage regulation (ΔVZ = 2.0 V), and RoHS-compliant e3 marking compatibility.
Technical Context
This device functions as a two-terminal voltage regulator in reverse-biased mode, maintaining stable output voltage across wide current variation (IZM = 49 mA at TL = 25°C). Its low dynamic impedance (44 Ω) ensures minimal voltage deviation under load transients, while its 25 °C/W junction-to-lead thermal resistance enables reliable 5 W operation with standard lead-length heat sinking.
The 1N5373B/TR8 exhibits tight voltage regulation (ΔVZ = 2.0 V between 10% and 50% of IZM), low knee impedance (70 Ω at 1 mA), and high surge current capability (500 A, 8.3 ms half-sine). Its cathode band polarity and T-18 package support manual and automated through-hole assembly on FR4 PCBs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 68 V ±5% - precise regulation point for feedback networks requiring stable reference under varying load |
| Test Current (IZT) | 20 mA - operating point where VZ and ZZ are specified; defines optimal bias for regulation accuracy |
| Dynamic Impedance (ZZ) | 44 Ω max - low AC resistance ensures minimal output voltage shift during current transients |
| Max Reverse Leakage (IR) | 0.5 μA at 51.7 V - negligible standby current in high-impedance sensing or battery-critical circuits |
| Max Regulator Current (IZM) | 49 mA - maximum continuous DC current at 25°C lead temperature; derates linearly above 25°C |
| Surge Current (IZSM) | 500 A (8.3 ms half-sine) - withstands transient overvoltage events without degradation |
| Voltage Regulation (ΔVZ) | 2.0 V - difference between VZ measured at 10% and 50% of IZM; quantifies regulation linearity |
Pinout & Package
Package: T-18 axial-leaded plastic encapsulated case per JEDEC DO-204AL, void-free thermosetting epoxy body (UL94V-0), tin-lead or RoHS-compliant matte-tin plating, cathode indicated by band, weight 0.7 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-voltage side in reverse-bias regulation | Connected to circuit ground or lower-potential node when used as shunt regulator |
| Cathode | Zener breakdown terminal / regulated output node | Banded end; connected to unregulated input rail; delivers stable 68 V reference to feedback path |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered Zener family | Ensures standardized mechanical dimensions, electrical behavior, and interchangeability across qualified suppliers |
| Moisture sensitivity Level 1 | No dry pack required prior to soldering; simplifies handling and eliminates bake-out steps |
| Nonsensitive to ESD (MIL-STD-750 Method 1020) | Robust handling in non-ESD-controlled environments without performance degradation |
| RoHS-compliant e3 marking option | Meets environmental compliance requirements for industrial and commercial applications |
| High surge current rating | 500 A peak withstand capability supports use in transient-prone power rails and protection circuits |
Applications
| Switch-Mode Power Supply Feedback | Overvoltage Clamp Circuit |
|---|---|
Use Scenario: Used in the optocoupler feedback path of an isolated 48 V DC-DC converter to regulate output voltage. IC Role / Device Role / Timing Role: Shunt voltage reference providing precise 68 V threshold to TL431-like control IC. Use Value: Enables ±1% output regulation via stable 68 V reference despite input ripple and load step changes. | Use Scenario: Placed across a 60 V bus to protect downstream MOSFET gates from transient spikes. IC Role / Device Role / Timing Role: Passive clamping element diverting excess energy to ground when bus exceeds 68 V. Use Value: Limits peak voltage to 68 V + dynamic overshoot margin, preventing gate oxide breakdown in 65 V-rated FETs. |
| Industrial Sensor Excitation Reference | Programmable Voltage Monitor Input |
Use Scenario: Supplies excitation voltage to a 4–20 mA pressure transducer requiring stable 68 V bias. IC Role / Device Role / Timing Role: Precision Zener reference generating fixed bias for sensor bridge circuitry. Use Value: Maintains excitation stability within ±0.34 V (±5%) over –40°C to +85°C ambient, ensuring calibrated output. | Use Scenario: Connected to comparator input to trigger shutdown when system voltage exceeds safe limit. IC Role / Device Role / Timing Role: Threshold-setting element defining trip point for undervoltage/overvoltage detection. Use Value: Provides repeatable 68 V activation threshold with <2.0 V hysteresis (ΔVZ), minimizing false triggers. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5373B (bulk) | Identical electrical specs and T-18 package; differs only in packaging format (tape-and-reel TR8 vs. bulk) | No functional difference; TR8 enables automated pick-and-place; bulk suits hand-solder prototyping | Select 1N5373B/TR8 for SMT line integration; choose bulk for low-volume evaluation |
| MMBZ5263B (SOT-23) | Same 68 V ±5%, but 0.35 W rating, 100 Ω ZZ, and surface-mount SOT-23 package | Limited to low-power signal-level regulation; unsuitable for 5 W dissipation or high-surge environments | Use MMBZ5263B only in space-constrained, low-current (<5 mA) applications where thermal mass is not required |
Compared with 1N5373B/TR8, the bulk version offers identical performance with manual handling convenience, while MMBZ5263B trades power capability and surge robustness for miniaturization-making it viable only where 5 W regulation and 500 A surge immunity are unnecessary.
Availability
1N5373B/TR8 is available at Aetrix Electronics and suitable for switch-mode power supplies, overvoltage protection circuits, and industrial sensor excitation systems requiring stable component supply, long-term lifecycle continuity, and RoHS-compliant sourcing.
Supply support for 1N5373B/TR8 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, mixed-signal, and RF solutions for aerospace, defense, and industrial markets.
The 1N53xxB series was designed for ruggedized voltage regulation in harsh-environment power systems, emphasizing thermal robustness, surge resilience, and JEDEC-standardized interchangeability.
FAQ
What is the Zener voltage tolerance of the 1N5373B/TR8?
The 1N5373B/TR8 has a nominal Zener voltage of 68 V with a tolerance of ±5%, as indicated by the "B" suffix per Microsemi's documentation. This tolerance applies across the full operating temperature range of –65°C to +150°C and is verified at 25°C lead temperature with 20 mA test current. The 1N5373B/TR8 does not support tighter tolerances like ±1% or ±2%-those require C or D suffix variants such as 1N5373C/TR8.
Can the 1N5373B/TR8 be used in surface-mount designs?
No, the 1N5373B/TR8 uses a T-18 axial-leaded package and is intended for through-hole mounting. Surface-mount equivalents exist-for example, SMBJ5373B-but they differ in package (DO-214AA), thermal performance, and surge rating. Substituting 1N5373B/TR8 into an SMT footprint would require mechanical adaptation and invalidate thermal and reliability specifications.
What is the maximum power dissipation of the 1N5373B/TR8 at 25°C?
The 1N5373B/TR8 is rated for 5.0 W steady-state power dissipation at 25°C lead temperature (TL), measured 3/8 inch (10 mm) from the body. When mounted on a standard FR4 PCB with 1 oz copper, its power rating drops to 1.47 W at 25°C ambient due to higher junction-to-ambient thermal resistance (85 °C/W). Derating curves in the datasheet must be applied for operation above 25°C.
Does the 1N5373B/TR8 meet RoHS requirements?
Yes, the 1N5373B/TR8 carries the "e3" suffix per Microsemi's documentation, indicating full RoHS compliance with lead-free matte-tin plating and halogen-free epoxy encapsulation. It satisfies EU Directive 2011/65/EU and related amendments, and is suitable for commercial and industrial applications requiring environmentally compliant components.
What is the reverse leakage current specification for the 1N5373B/TR8?
The 1N5373B/TR8 specifies a maximum reverse leakage current (IR) of 0.5 μA at a reverse test voltage (VR) of 51.7 V-corresponding to 75% of its nominal Zener voltage. This low leakage supports high-impedance reference applications and minimizes standby power loss in battery-backed or energy-sensitive circuits using the 1N5373B/TR8.
1N5373B/TR8 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):
- 68 V
- Tolerance:
- ±5%
- Power - Max:
- 5 W
- Impedance (Max) (Zzt):
- 44 Ohms
- Current - Reverse Leakage @ Vr:
- 500 nA @ 49 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
1N5373B/TR8 FAQ
1.How can I place an order for 1N5373B/TR8 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5373B/TR8 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 1N5373B/TR8 reliable?
The price and inventory of 1N5373B/TR8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5373B/TR8 is usually 5 days.
3.What payment methods are accepted for 1N5373B/TR8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5373B/TR8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5373B/TR8?
1N5373B/TR8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5373B/TR8 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 1N5373B/TR8?
For technical support, including 1N5373B/TR8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5373B/TR8 requirements.
6.How does Aetrix verify that 1N5373B/TR8 is sourced from the original manufacturer or authorized distributors?
All 1N5373B/TR8 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 1N5373B/TR8 meets industry standards.
7.What is the process for return or replacement of 1N5373B/TR8?
All 1N5373B/TR8 units undergo pre-shipment inspection (PSI). If there is an issue with 1N5373B/TR8, 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 1N5373B/TR8 part is unused and in its original packaging.
Return procedure for 1N5373B/TR8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5373B/TR8 Tags
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MM5Z5V1ST1G
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