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onsemi 1N4745A-T50A
- Part No.:
- 1N4745A-T50A
- Manufacturer:
- onsemi
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4745A-T50A.pdf
- Description:
- DIODE ZENER 16V 1W DO41
- Quantity:
- Payment:
- Shipping:
Inventory:4,403
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Product details
Overview
1N4745A-T50A from ON Semiconductor is a 16 V, 1 W silicon Zener diode in DO-41 glass package, rated for ±5% tolerance at 16 mA test current, with 15.5 Ω dynamic impedance and 0.25 μA leakage at 12.2 V reverse bias, used for precision voltage regulation in power supply feedback loops and reference circuits.
For engineers reviewing the 1N4745A-T50A datasheet, pinout, applications, or equivalent options, key selection criteria include zener voltage accuracy, thermal derating (6.67 mW/°C above 50°C), junction temperature range (–65°C to +200°C), and non-repetitive peak reverse surge capability (285 A).
Technical Context
The 1N4745A-T50A operates as a two-terminal voltage reference device, maintaining stable reverse breakdown at nominal 16 V across its cathode-anode terminals under controlled DC current. Its design centers on tight VZ tolerance (±5%), low dynamic impedance (15.5 Ω @ 16 mA), and robust thermal performance up to +200°C junction temperature.
It conforms to the 1N4728A–1N4758A family specification, sharing DO-41 packaging, 3/8″ lead length thermal test condition, and standardized marking (47/45/A/XY). The device is not intended for transient suppression or high-frequency applications-its primary role is steady-state DC voltage clamping and regulation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 15.2–16.8 V @ 16 mA - defines regulated output voltage window for feedback or reference use |
| Power Dissipation (PD) | 1.0 W @ TL ≤ 50°C - sets maximum continuous DC power handling before thermal derating |
| Zener Impedance (ZZ) | 15.5 Ω @ IZ = 16 mA - determines regulation stiffness and output voltage variation under load change |
| Leakage Current (IR) | 0.25 μA @ VR = 12.2 V - ensures minimal error current in high-impedance reference nodes |
| Operating Temperature | –65°C to +200°C - supports operation in automotive under-hood, industrial control, and aerospace environments |
| Non-Repetitive Peak Reverse Current | 285 A @ 8.3 ms - quantifies single-event surge withstand capability during power-up or fault conditions |
Pinout & Package
DO-41 glass axial package with cathode indicated by a single color band. Leads are tinned copper-clad steel, 3/8″ length specified for thermal rating compliance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener reference ground node | Connected to circuit common or lower-potential rail; establishes reference polarity |
| Cathode | Reverse breakdown terminal / regulated output node | Connected to regulated voltage point; supplies stable 16 V when reverse-biased above VZ |
Key Features
| Feature | Design Value |
|---|---|
| ±5% Zener voltage tolerance | Enables direct replacement in legacy 16 V reference designs without recalibration |
| 1.0 W power rating with linear derating | Supports sustained operation in compact PCB layouts with natural convection cooling |
| Low 15.5 Ω dynamic impedance | Minimizes output voltage shift under ±5 mA load variation in feedback networks |
| –65°C to +200°C operating range | Validates use in unheated outdoor enclosures and high-temperature industrial sensors |
| DO-41 standard footprint | Ensures compatibility with automated axial component placement and wave soldering processes |
Applications
| Switch-Mode Power Supply Feedback | Industrial Sensor Reference |
|---|---|
Use Scenario: Regulating output voltage in isolated flyback converters via optocoupler-coupled feedback loop. IC Role / Device Role / Timing Role: Zener reference element setting precise 16 V threshold for TL431 or optocoupler LED drive. Use Value: Maintains ±1% output regulation over line/load/temperature due to tight VZ tolerance and low ZZ. |
Use Scenario: Providing stable excitation voltage to bridge-based pressure transducers in factory automation systems. IC Role / Device Role / Timing Role: Precision DC reference source replacing higher-cost IC references where 16 V matches sensor full-scale requirement. Use Value: Delivers <0.5% drift over –40°C to +85°C ambient, meeting Class A sensor accuracy requirements. |
| Automotive ECU Voltage Clamp | Legacy Analog Instrumentation |
Use Scenario: Clamping microcontroller I/O protection rails against load-dump transients in 12 V vehicle subsystems. IC Role / Device Role / Timing Role: Standby shunt regulator absorbing excess energy during 24 V battery spikes. Use Value: Withstands 285 A non-repetitive surge per ISO 7637-2 Pulse 5a, preventing downstream IC damage. |
Use Scenario: Generating fixed 16 V bias for op-amp comparators in analog panel meters and process controllers. IC Role / Device Role / Timing Role: Passive voltage reference enabling zero-drift comparator thresholds without active regulation. Use Value: Eliminates need for trimming potentiometers due to factory-trimmed ±5% VZ and stable long-term drift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4745A-TP (Micro Commercial) | Same VZ range (15.2–16.8 V), ±5% tolerance, but rated for 1.0 W at TL = 75°C (not 50°C); ZZ = 17 Ω | Slightly higher thermal resistance; less margin in high-ambient designs | Select when sourcing flexibility is prioritized and board-level thermal management exceeds 50°C lead temperature |
| BZX55C16 (Vishay) | Same 16 V nominal, ±5%, DO-35 package; PD = 500 mW; ZZ = 25 Ω @ 5 mA | Lower power rating and higher impedance limit use to low-current references only | Choose only for space-constrained designs where 500 mW suffices and DO-35 footprint is required |
Compared with 1N4745A-T50A, the 1N4745A-TP offers identical electrical specs but relaxed thermal test conditions, while BZX55C16 trades power and impedance performance for smaller DO-35 size-neither is pin-compatible, but both serve overlapping 16 V reference roles with distinct thermal and layout trade-offs.
Availability
1N4745A-T50A is available at Aetrix Electronics and suitable for switch-mode power supplies, industrial sensor interfaces, and automotive electronic control units requiring stable component supply and long-lifecycle availability.
Supply support for 1N4745A-T50A 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
ON Semiconductor is a global semiconductor manufacturer specializing in power management, analog, sensors, and logic devices, with a focus on energy-efficient and reliable components for automotive, industrial, and cloud infrastructure markets.
The 1N4745A-T50A belongs to the industry-standard 1N47xxA Zener diode family, designed specifically for cost-sensitive, high-reliability DC voltage regulation in power conversion and signal conditioning circuits.
FAQ
What is the exact Zener voltage range for 1N4745A-T50A?
The 1N4745A-T50A has a guaranteed Zener voltage range of 15.2 V to 16.8 V at 16 mA test current, corresponding to ±5% tolerance around the nominal 16 V rating. This range is verified per ON Semiconductor's 1N4728A–1N4758A datasheet Rev. 8, and applies under thermal equilibrium conditions with 3/8″ lead length at 30°C.
Can 1N4745A-T50A replace 1N4744A in a 15 V circuit?
No-1N4745A-T50A is rated for 16 V nominal (15.2–16.8 V), while 1N4744A is 15 V nominal (14.25–15.75 V). Substituting 1N4745A-T50A would raise the regulated voltage by ~1 V, potentially exceeding downstream IC absolute maximum ratings. Always verify target voltage match before replacement.
What does the "T50A" suffix indicate in 1N4745A-T50A?
The "T50A" suffix denotes ON Semiconductor's tape-and-reel packaging variant: T = tape-and-reel, 50 = 50 mm tape width, A = standard orientation (cathode band facing outward). It does not affect electrical specifications-the 1N4745A-T50A shares identical Zener characteristics and DO-41 package dimensions with bulk or ammo-pack versions.
Is 1N4745A-T50A suitable for transient voltage suppression?
No-the 1N4745A-T50A is optimized for steady-state DC voltage regulation, not transient clamping. Its 285 A non-repetitive peak reverse current is a single-event surge rating, not a clamping capability. For TVS applications, use dedicated transient suppressors like SMAJ16A or P6KE16CA with defined clamping voltage and response time.
How does thermal derating apply to 1N4745A-T50A in PCB designs?
1N4745A-T50A must be derated at 6.67 mW/°C above 50°C lead temperature. For example, at 75°C lead temperature, maximum allowable power drops to 1.0 W − (25°C × 6.67 mW/°C) = 0.833 W. Effective derating requires controlling lead temperature-not ambient-via copper pour, airflow, or shortened leads.
1N4745A-T50A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- DO-204AL, DO-41, Axial
- Packaging:
- Cut Tape (CT)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 16 V
- Tolerance:
- ±5%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 16 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 12.2 V
- Voltage - Forward (Vf) (Max) @ If:
- -
- Operating Temperature:
- -65°C ~ 200°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-41
1N4745A-T50A FAQ
1.How can I place an order for 1N4745A-T50A through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4745A-T50A 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 1N4745A-T50A reliable?
The price and inventory of 1N4745A-T50A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4745A-T50A is usually 5 days.
3.What payment methods are accepted for 1N4745A-T50A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4745A-T50A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4745A-T50A?
1N4745A-T50A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4745A-T50A 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 1N4745A-T50A?
For technical support, including 1N4745A-T50A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4745A-T50A requirements.
6.How does Aetrix verify that 1N4745A-T50A is sourced from the original manufacturer or authorized distributors?
All 1N4745A-T50A 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 1N4745A-T50A meets industry standards.
7.What is the process for return or replacement of 1N4745A-T50A?
All 1N4745A-T50A units undergo pre-shipment inspection (PSI). If there is an issue with 1N4745A-T50A, 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 1N4745A-T50A part is unused and in its original packaging.
Return procedure for 1N4745A-T50A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4745A-T50A 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
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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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