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Microchip Technology 1N4745P/TR12
- Part No.:
- 1N4745P/TR12
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4745P/TR12.pdf
- Description:
- DIODE ZENER 16V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:9,746
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Product details
Overview
1N4745P/TR12 from Microsemi is a 16 V, 1 W plastic-encapsulated Zener diode with ±5% voltage tolerance, 15.5 mA test current (IZT), 16 Ω dynamic impedance (ZZT), and DO-41 package. It regulates voltage in power supply reference and overvoltage protection circuits across -65°C to +150°C operating range.
For engineers reviewing the 1N4745P/TR12 datasheet, 1N4745P/TR12 pinout, 1N4745P/TR12 application, or 1N4745P/TR12 equivalent, key selection criteria include Zener voltage accuracy, thermal resistance (45°C/W junction-to-lead), surge current rating (285 mA), reverse leakage (5 µA at 12.2 V), and RoHS-compliant "e3" plating option.
Technical Context
This discrete Zener diode operates in reverse breakdown to maintain stable voltage under varying load and temperature conditions. Its 16 V nominal Zener voltage is specified at 15.5 mA test current with 16 Ω dynamic impedance, ensuring predictable regulation knee behavior per JEDEC 1N47xxA standards.
The DO-41 axial-leaded plastic package delivers 45°C/W junction-to-lead thermal resistance at 10 mm lead length and supports 1.0 W steady-state dissipation below 105°C lead temperature. Polarity is marked by cathode band; operation requires cathode-positive bias for regulation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (Vz) | 16 V ±5% at 15.5 mA - defines precise regulation point for reference design |
| Power Dissipation | 1.0 W at TL < 105°C - sets maximum continuous thermal load on PCB trace |
| Dynamic Impedance | 16 Ω at IZT - determines output voltage variation under load current changes |
| Reverse Leakage | 5 µA max at 12.2 V - ensures low standby power loss in high-impedance bias networks |
| Surge Current | 285 mA (½-sine, 1/120 s) - withstands transient overvoltage events without degradation |
| Thermal Resistance | 45°C/W junction-to-lead - enables thermal design with standard 3/8" lead length mounting |
| Operating Temp | -65°C to +150°C - supports industrial and automotive under-hood applications |
Pinout & Package
DO-41 (DO-204AL) plastic axial-leaded package with cathode indicated by colored band; leads are tin-lead or RoHS-compliant matte-tin plated per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Reverse-biased input terminal | Connected to lower-potential node; carries full Zener current during regulation |
| Cathode | Regulated output terminal | Banded end; held at stable 16 V above anode when reverse-biased above breakdown |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC 1N47xxA Registration | Guarantees interoperability with legacy designs using industry-standard footprint and specs |
| Moisture Sensitivity Level 1 | Enables direct assembly without dry-pack baking or floor-life tracking |
| Nonsensitive to ESD | Withstands handling per MIL-STD-750 Method 1020 without parameter shift or failure |
| RoHS Compliant Option | "e3" suffix denotes annealed matte-tin plating compatible with lead-free reflow |
Applications
| Power Supply Reference | Overvoltage Protection |
|---|---|
Use Scenario: Stabilizing feedback voltage in linear regulator error amplifiers or switching converter references. IC Role / Device Role / Timing Role: Zener diode provides fixed 16 V reference point for comparator or op-amp input. Use Value: ±5% tolerance and 16 Ω dynamic impedance ensure <±0.8 V output variation across load current changes. | Use Scenario: Clamping transient spikes on DC rails in motor drives or industrial I/O modules. IC Role / Device Role / Timing Role: Shunts excess energy to ground when rail exceeds 16 V, protecting downstream ICs. Use Value: 285 mA surge rating handles repetitive 1/120 s transients without parametric drift. |
| Voltage Monitor Threshold | Signal Level Translation |
Use Scenario: Detecting undervoltage or overvoltage conditions in battery management systems. IC Role / Device Role / Timing Role: Forms threshold element in comparator circuit comparing sensed voltage against 16 V reference. Use Value: -65°C to +150°C operating range ensures reliable trip-point stability across environmental extremes. | Use Scenario: Biasing logic-level interfaces between 3.3 V, 5 V, and 12 V domains. IC Role / Device Role / Timing Role: Sets clamped high-level voltage for open-collector or level-shifting transistor stages. Use Value: Low 5 µA reverse leakage at 12.2 V minimizes quiescent current in always-on monitoring paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4745A | No "P" suffix; glass-body DO-35 package, higher thermal resistance (65°C/W) | Less suitable for high-power-density layouts due to inferior heat dissipation | Select 1N4745P/TR12 for plastic encapsulation, lower RθJL, and tape-and-reel convenience |
| MMSZ4705T1G | Surface-mount SOD-123 package, same 16 V/5%, but rated at 500 mW not 1 W | Not interchangeable in 1 W thermal designs; limited surge capability (150 mA) | Choose MMSZ4705T1G only for space-constrained, lower-power SMT applications |
Compared with 1N4745A and MMSZ4705T1G, the 1N4745P/TR12 offers superior thermal performance in through-hole layouts and higher surge robustness, making it optimal for industrial power rails where reliability under transient stress is critical.
Availability
1N4745P/TR12 is available at Aetrix Electronics and suitable for power supply reference, overvoltage protection, voltage monitor threshold, and signal level translation applications requiring stable component supply and long-term obsolescence management.
Supply support for 1N4745P/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 1N47xxA series was designed for general-purpose voltage regulation in ruggedized power systems, emphasizing JEDEC compatibility, wide temperature operation, and screening flexibility for military-grade applications.
FAQ
What is the Zener voltage tolerance of the 1N4745P/TR12?
The 1N4745P/TR12 has a nominal Zener voltage of 16 V with a ±5% tolerance, as indicated by the "A" suffix in its JEDEC designation. This means the actual breakdown voltage falls between 15.2 V and 16.8 V when measured at 15.5 mA test current and 25°C lead temperature. The tolerance is guaranteed per Microsemi's published electrical characteristics table and applies to all units in the 1N4745P/TR12 production lot.
Does the 1N4745P/TR12 have RoHS-compliant packaging?
Yes, the 1N4745P/TR12 is offered in RoHS-compliant form with "e3" suffix plating-annealed matte-tin terminals compliant with J-STD-609. The base device uses void-free thermosetting epoxy meeting UL94V-0, and the TR12 tape-and-reel packaging adheres to EIA-296 standards. Full RoHS documentation is available upon request from Aetrix Electronics for compliance validation.
What is the maximum surge current rating for the 1N4745P/TR12?
The 1N4745P/TR12 has a maximum non-repetitive surge current (ISM) of 285 mA, measured using a ½-sine wave pulse of 1/120 second duration at 25°C ambient. This rating reflects its ability to absorb transient energy without parametric shift or failure, supporting use in DC rail clamping where short-duration overvoltages occur, such as in relay coil suppression or inductive load switching.
How does the thermal resistance of the 1N4745P/TR12 compare to glass-body variants?
The 1N4745P/TR12 exhibits 45°C/W junction-to-lead thermal resistance at 10 mm lead length, significantly lower than the 65°C/W of the glass-body 1N4745A. This 31% improvement enables higher sustained power dissipation in compact layouts and reduces thermal stress on adjacent components. The plastic encapsulation also eliminates moisture sensitivity concerns present in older glass packages.
Can the 1N4745P/TR12 be used in surface-mount designs?
No, the 1N4745P/TR12 is a DO-41 axial-leaded through-hole device and is not suitable for surface-mount assembly. For SMT equivalents, Microsemi offers the SMAJ4745A (SMA package) and MLL4745A (SOD-123), both rated at 16 V/5% but with different power ratings and thermal profiles. Substitution requires PCB redesign and validation of thermal and surge performance in the target layout.
1N4745P/TR12 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-204AL, DO-41, Axial
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Voltage - Zener (Nom) (Vz):
- 16 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 16 Ohms
- Current - Reverse Leakage @ Vr:
- 5 µA @ 12.2 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -65°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- DO-204AL (DO-41)
1N4745P/TR12 FAQ
1.How can I place an order for 1N4745P/TR12 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4745P/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 1N4745P/TR12 reliable?
The price and inventory of 1N4745P/TR12 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4745P/TR12 is usually 5 days.
3.What payment methods are accepted for 1N4745P/TR12?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4745P/TR12 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4745P/TR12?
1N4745P/TR12 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4745P/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 1N4745P/TR12?
For technical support, including 1N4745P/TR12 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4745P/TR12 requirements.
6.How does Aetrix verify that 1N4745P/TR12 is sourced from the original manufacturer or authorized distributors?
All 1N4745P/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 1N4745P/TR12 meets industry standards.
7.What is the process for return or replacement of 1N4745P/TR12?
All 1N4745P/TR12 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4745P/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 1N4745P/TR12 part is unused and in its original packaging.
Return procedure for 1N4745P/TR12:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4745P/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
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BZX84C3V3LT1G
onsemi
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MMSZ5245BS-7-F
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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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