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Microchip Technology 1N5373E3/TR8
- Part No.:
- 1N5373E3/TR8
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- T-18, Axial
- Datasheet:
-
1N5373E3/TR8.pdf
- Description:
- DIODE ZENER 68V 5W T18
- Quantity:
- Payment:
- Shipping:
Inventory:9,913
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Product details
Overview
1N5373E3/TR8 from Microsemi is a 5 W axial-leaded silicon Zener diode with nominal regulation voltage of 68 V, ±5% tolerance (B-suffix equivalent), 20 mA test current, 44 Ω maximum dynamic impedance at IZT, and 0.5 μA maximum reverse leakage at 51.7 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 1N5373E3/TR8 datasheet, 1N5373E3/TR8 pinout, 1N5373E3/TR8 application, or 1N5373E3/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 matte-tin plating per MIL-STD-750.
Technical Context
This device functions as a two-terminal voltage regulator operating in reverse breakdown mode. Its Zener voltage is specified at 25 °C with 40 ms DC measurement delay and defined by ±5% tolerance across the full operating temperature range. The low dynamic impedance (44 Ω) ensures stable regulation under varying load currents.
Thermal design relies on lead-length-dependent junction-to-lead resistance (25 °C/W at 3/8″ lead length) rather than ambient-based dissipation. Reverse leakage is guaranteed ≤0.5 μA at VR = 51.7 V (75% of VZ), and surge capability is rated for non-repetitive 8.3 ms half-sine wave peaks up to 500 A.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 68 V nominal, ±5% tolerance - defines precise clamping threshold for overvoltage protection circuits |
| Power Dissipation | 5.0 W at TL = 25 °C with 3/8″ lead length - requires mechanical heat sinking for sustained operation |
| Test Current (IZT) | 20 mA - standard bias point for VZ measurement and impedance characterization |
| Dynamic Impedance (ZZ) | 44 Ω max at IZT - determines output voltage variation under load current changes |
| Reverse Leakage (IR) | ≤0.5 μA at VR = 51.7 V - ensures minimal standby power loss in high-impedance bias networks |
| Surge Current (IZSM) | 500 A peak (8.3 ms half-sine) - supports transient suppression without failure in power rail protection |
| Voltage Regulation (ΔVZ) | 2.0 V - difference between VZ measured at 10% and 50% of IZM, indicating regulation linearity |
Pinout & Package
Package: Axial-leaded T-18 plastic case (void-free UL94V-0 epoxy), cathode indicated by band; leads plated with RoHS-compliant annealed matte tin per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-voltage reference node | Connected to circuit ground or lower-potential rail during Zener operation |
| Cathode | Zener breakdown terminal / regulated output node | Banded end; connected to unregulated input rail to clamp voltage at 68 V |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered Zener | Complies with industry-standard 1N53xxB series 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 - safe for manual handling without special precautions |
| High Surge Withstand | 500 A peak surge rating enables robust transient suppression without derating |
| RoHS Compliant (e3 suffix) | Meets EU Directive 2011/65/EU with matte-tin plating - no lead or hazardous substances |
Applications
| Industrial Power Supply Regulation | Automotive ECU Voltage Reference |
|---|---|
Use Scenario: Stabilizing feedback voltage in isolated flyback converter auxiliary windings. IC Role / Device Role / Timing Role: Zener diode providing fixed 68 V reference to optocoupler LED drive circuit. Use Value: Maintains ±5% output regulation across line/load transients and –40 °C to +125 °C ambient due to low ΔVZ and stable VZ temperature coefficient. | Use Scenario: Clamping microcontroller supply rail against load-dump spikes in 24 V vehicle systems. IC Role / Device Role / Timing Role: Overvoltage protector shunting excess energy to ground during ISO 7637-2 Pulse 5a events. Use Value: Survives 500 A surge peaks without degradation, enabling single-device protection without external TVS stacking. |
| Programmable Logic Controller I/O Protection | Telecom Line Card Surge Suppression |
Use Scenario: Protecting 24 V digital input channels from field-wiring induced transients. IC Role / Device Role / Timing Role: Primary clamping element in series-connected protection network with current-limiting resistor. Use Value: Low 44 Ω dynamic impedance ensures fast response and minimal overshoot during 1 kV/μs surges per IEC 61000-4-5. | Use Scenario: Secondary surge protection stage after gas discharge tube (GDT) in POTS line interface. IC Role / Device Role / Timing Role: Precision voltage limiter defining maximum allowable voltage on SLIC front-end. Use Value: Tight ±5% tolerance and 2.0 V ΔVZ enable predictable clamping window aligned with SLIC absolute maximum ratings. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N5373B | Same VZ (68 V), ±5%, but non-RoHS tin-lead plating; identical electrical specs and package | Not suitable for RoHS-compliant production; requires leaded solder process compatibility | Select when legacy assembly lines use SnPb solder and exemption from RoHS applies |
| MMSZ5259ET1G | Surface-mount SOD-123 package; 68 V, ±5%, 500 mW rating - not power-equivalent | Limited to low-power bias/reference roles; cannot replace 1N5373E3/TR8 in 5 W surge applications | Choose only for space-constrained PCBs where thermal mass and surge duty are negligible |
Compared with 1N5373B and MMSZ5259ET1G, the 1N5373E3/TR8 uniquely combines RoHS compliance, 5 W power handling, axial-leaded through-hole mounting, and JEDEC-standardized mechanical dimensions - making it irreplaceable in high-reliability industrial power designs requiring proven surge resilience and moisture-insensitive handling.
Availability
1N5373E3/TR8 is available at Aetrix Electronics and suitable for industrial power supplies, automotive ECUs, programmable logic controller I/O modules, and telecom line card protection requiring stable component supply and long-term manufacturability.
Supply support for 1N5373E3/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, RF, and timing solutions for aerospace, defense, and industrial markets.
The 1N53xx series was designed specifically for ruggedized voltage regulation and transient suppression in harsh-environment power systems where long-term stability, surge survivability, and JEDEC-standard interchangeability are mandatory.
FAQ
What is the Zener voltage tolerance for 1N5373E3/TR8?
The 1N5373E3/TR8 has a nominal Zener voltage of 68 V with ±5% tolerance, consistent with the "B" suffix designation in the 1N53xxB family. This tolerance is verified at 25 °C with 40 ms DC measurement delay and applies across the full operating temperature range of –65 °C to +150 °C. The e3 suffix indicates RoHS compliance but does not affect voltage tolerance.
Can 1N5373E3/TR8 be used in surface-mount designs?
No, the 1N5373E3/TR8 is an axial-leaded T-18 package device intended for through-hole mounting. Microsemi offers surface-mount equivalents such as SMBJ5373B for similar voltage ratings, but those differ in package, thermal performance, and surge capability. Direct substitution into SMT layouts is not feasible without board redesign and thermal validation.
What is the maximum steady-state power dissipation for 1N5373E3/TR8 on a standard PCB?
When mounted on FR4 with 1 oz copper, 4 mm² pads, and 1 mm × 25 mm traces, the 1N5373E3/TR8 delivers 1.47 W steady-state power at TA = 25 °C. This is significantly lower than its 5 W rating at TL = 25 °C (3/8″ lead length), reflecting higher thermal resistance to ambient (85 °C/W). Adequate copper area and airflow are essential for sustained operation above 1 W.
Does 1N5373E3/TR8 require dry packing before reflow soldering?
No, the 1N5373E3/TR8 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 and Level 1 classification eliminate handling restrictions associated with humidity-induced popcorning during reflow.
How is the voltage regulation (ΔVZ) of 1N5373E3/TR8 defined and measured?
Voltage regulation (ΔVZ) for the 1N5373E3/TR8 is defined as the difference between Zener voltage measured at 10% and 50% of maximum Zener current (IZM), yielding 2.0 V. This parameter quantifies regulation linearity under varying load conditions and is measured using DC current sources at TL = 25 °C, not AC or pulsed methods.
1N5373E3/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:
- ±20%
- 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
1N5373E3/TR8 FAQ
1.How can I place an order for 1N5373E3/TR8 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N5373E3/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 1N5373E3/TR8 reliable?
The price and inventory of 1N5373E3/TR8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N5373E3/TR8 is usually 5 days.
3.What payment methods are accepted for 1N5373E3/TR8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N5373E3/TR8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N5373E3/TR8?
1N5373E3/TR8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N5373E3/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 1N5373E3/TR8?
For technical support, including 1N5373E3/TR8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N5373E3/TR8 requirements.
6.How does Aetrix verify that 1N5373E3/TR8 is sourced from the original manufacturer or authorized distributors?
All 1N5373E3/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 1N5373E3/TR8 meets industry standards.
7.What is the process for return or replacement of 1N5373E3/TR8?
All 1N5373E3/TR8 units undergo pre-shipment inspection (PSI). If there is an issue with 1N5373E3/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 1N5373E3/TR8 part is unused and in its original packaging.
Return procedure for 1N5373E3/TR8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N5373E3/TR8 Tags
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