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Microchip Technology 1N4745P/TR8
- Part No.:
- 1N4745P/TR8
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4745P/TR8.pdf
- Description:
- DIODE ZENER 16V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:4,664
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Product details
Overview
1N4745P/TR8 from Microsemi is a 16 V, 1 W silicon Zener diode in DO-41 plastic package with ±5% voltage tolerance, 15.5 mA test current (IZT), and 16 Ω dynamic impedance (ZZT) at IZT-used for precision voltage regulation in power supply reference and overvoltage protection circuits.
For engineers reviewing the 1N4745P/TR8 datasheet, 1N4745P/TR8 pinout, 1N4745P/TR8 application, or 1N4745P/TR8 equivalent, key selection factors 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
The 1N4745P/TR8 operates in reverse breakdown to maintain stable 16 V output across a wide current range (0.25–15.5 mA), with sharp knee characteristics verified by dual-point Zener impedance measurement per MicroNote 202. Its DO-41 plastic encapsulation delivers lower thermal resistance than glass-body variants (G suffix) and meets IPC/JEDEC J-STD-020B Level 1 moisture sensitivity without dry pack.
Designed for axial-lead mounting, it features tin-lead or matte-tin plating compliant with MIL-STD-750 Method 2026, cathode band polarity marking, and 1.2 V forward voltage max at 200 mA-enabling reliable bidirectional use in clamp and reference topologies under industrial temperature conditions (–65 °C to +150 °C).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 16 V ±5% at 15.5 mA - defines regulated output level with tight tolerance for reference stability |
| Power Dissipation | 1.0 W at 25 °C - sets maximum continuous DC power handling before thermal derating |
| Dynamic Impedance (ZZT) | 16 Ω at IZT = 15.5 mA - indicates low AC impedance for minimal output voltage variation under load transients |
| Reverse Leakage Current | 5 µA max at 12.2 V - ensures low standby power loss in high-impedance bias networks |
| Surge Current (ISM) | 285 mA (½-sine, 1/120 s) - supports transient overvoltage clamping without degradation |
| Thermal Resistance | 45 °C/W junction-to-lead (3/8″ lead length) - enables accurate thermal design for PCB trace heatsinking |
| Operating Temperature | –65 °C to +150 °C - qualifies for automotive under-hood and industrial control environments |
Pinout & Package
DO-41 (DO-204AL) plastic axial-leaded package with void-free UL94V-0 epoxy body, cathode indicated by colored band; terminals are tin-lead or RoHS-compliant matte-tin plated for solderability per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Non-banded end | Connected to circuit ground or lower potential node during Zener operation |
| Cathode | Banded end | Connected to regulated voltage node; must be held positive relative to anode for breakdown conduction |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered 1 W Zener | Industry-standard footprint and electrical behavior compatible with legacy designs and automated assembly |
| Plastic P-suffix construction | 45 °C/W junction-to-lead thermal resistance-15% lower than glass-body G-suffix equivalents for improved power handling |
| RoHS-compliant "e3" option | Matte-tin plating meets EU Directive 2011/65/EU and is solderable without lead-free process requalification |
| MIL-STD-750 ESD robustness | Nonsensitive to electrostatic discharge per Method 1020-eliminates need for special handling in production environments |
| Moisture Sensitivity Level 1 | No dry pack required per IPC/JEDEC J-STD-020B-reduces inventory management overhead and BOM cost |
Applications
| Power Supply Reference | Overvoltage Clamp |
|---|---|
Use Scenario: Stabilizing feedback voltage in linear regulator ICs or discrete op-amp references. IC Role / Device Role / Timing Role: Provides precise 16 V reference point for error amplifier comparison. Use Value: ±5% VZ tolerance and 16 Ω ZZT ensure <1% output drift across 1–15 mA load current range. | Use Scenario: Protecting microcontroller I/O pins from ESD or inductive kickback in motor drive circuits. IC Role / Device Role / Timing Role: Shunts transient energy above 16 V to ground before damage threshold is exceeded. Use Value: 285 mA surge rating and fast 1/120 s pulse response limit clamping voltage overshoot to ≤18.2 V. |
| Voltage Monitor Threshold | Current Source Bias |
Use Scenario: Triggering shutdown logic when battery voltage exceeds safe operating window in portable equipment. IC Role / Device Role / Timing Role: Serves as sensing element in comparator input network with hysteresis. Use Value: Sharp knee impedance (ZZK = 0.5 Ω at IZK = 0.25 mA) ensures clean transition at 16 V threshold. | Use Scenario: Generating stable bias current for transistor amplifiers or LED drivers via series resistor. IC Role / Device Role / Timing Role: Maintains constant voltage drop to produce predictable current through external resistor. Use Value: Low 1.2 V forward voltage max allows efficient bidirectional use in current mirror configurations. |
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 65 °C/W junction-to-ambient thermal resistance | Less suitable for high-power-density layouts where lead heatsinking is critical | Select 1N4745P/TR8 when board space permits axial leads and thermal performance is prioritized |
| BZX55C16 | 0.5 W rating, 16 V ±5%, DO-35 package; 40 Ω ZZT at 5 mA - higher impedance and lower power | Limited to low-current biasing; not rated for 285 mA surge events | Choose BZX55C16 only for space-constrained, low-power signal-level regulation |
Compared with 1N4745A and BZX55C16, the 1N4745P/TR8 delivers superior thermal management (45 °C/W), higher surge capability (285 mA), and plastic-package reliability-making it optimal for industrial power rails where long-term stability under thermal cycling matters.
Availability
1N4745P/TR8 is available at Aetrix Electronics and suitable for power supply reference, overvoltage protection, and voltage monitor threshold applications requiring stable component supply across extended production lifecycles.
Supply support for 1N4745P/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 and mixed-signal components for aerospace, defense, and industrial markets.
The 1N47xxAP series was engineered for ruggedized voltage regulation in mission-critical systems-emphasizing thermal robustness, ESD immunity, and JEDEC-standard compatibility across military and commercial grades.
FAQ
What is the Zener voltage tolerance of the 1N4745P/TR8?
The 1N4745P/TR8 has a nominal Zener voltage of 16 V with a ±5% tolerance, as indicated by the "A" suffix in its JEDEC designation. This tolerance is specified at 15.5 mA test current and 25 °C lead temperature. The 1N4745P/TR8 does not offer tighter 1% or 2% tolerances-those require "D" or "C" suffix variants like 1N4745D or 1N4745C, which are distinct orderable parts.
Does the 1N4745P/TR8 support RoHS compliance?
Yes, the 1N4745P/TR8 is available in RoHS-compliant form with the "e3" suffix (e.g., 1N4745P/TR8e3), featuring annealed matte-tin plating that meets EU Directive 2011/65/EU. Standard versions use tin-lead plating. Both meet MIL-STD-750 Method 2026 solderability requirements, and the "e3" variant requires no process change for lead-free reflow.
What is the maximum surge current rating for the 1N4745P/TR8?
The 1N4745P/TR8 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 applies only to single-event transients; repeated surges must respect average power limits and thermal derating curves shown in Figure 1 of the Microsemi datasheet.
How does the DO-41 plastic package of the 1N4745P/TR8 compare thermally to glass-body Zeners?
The DO-41 plastic package of the 1N4745P/TR8 achieves 45 °C/W junction-to-lead thermal resistance-significantly lower than the 65 °C/W typical of DO-35 glass-body equivalents like the 1N4745A. This 31% improvement enables higher sustained power dissipation in lead-heatsinked layouts and reduces thermal stress during transient overload conditions.
Can the 1N4745P/TR8 be used in surface-mount designs?
No, the 1N4745P/TR8 is an axial-leaded DO-41 device and is not surface-mount compatible. Microsemi offers surface-mount equivalents-such as SMAJ4745A (SMA package) and MLL4745A (SOD-123)-which share identical electrical specs but require different PCB footprints and reflow profiles. These alternatives are not drop-in replacements for the 1N4745P/TR8.
1N4745P/TR8 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/TR8 FAQ
1.How can I place an order for 1N4745P/TR8 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4745P/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 1N4745P/TR8 reliable?
The price and inventory of 1N4745P/TR8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4745P/TR8 is usually 5 days.
3.What payment methods are accepted for 1N4745P/TR8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4745P/TR8 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4745P/TR8?
1N4745P/TR8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4745P/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 1N4745P/TR8?
For technical support, including 1N4745P/TR8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4745P/TR8 requirements.
6.How does Aetrix verify that 1N4745P/TR8 is sourced from the original manufacturer or authorized distributors?
All 1N4745P/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 1N4745P/TR8 meets industry standards.
7.What is the process for return or replacement of 1N4745P/TR8?
All 1N4745P/TR8 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4745P/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 1N4745P/TR8 part is unused and in its original packaging.
Return procedure for 1N4745P/TR8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4745P/TR8 Tags
-
MMBZ5240B-7-F
Diodes Incorporated
-
BZT52C5V6T-7
Diodes Incorporated
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MMSZ5231B-7-F
Diodes Incorporated
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BZT52C15-7-F
Diodes Incorporated
-
BZX84C3V3LT1G
onsemi
-
MMSZ5245BS-7-F
Diodes Incorporated
-
MMSZ4682T1G
onsemi
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BZT52C15S-7-F
Diodes Incorporated
-
MM5Z5V1ST1G
onsemi
-
SMAJ4744A-TP
Micro Commercial Co
-
BZT52C3V6LP-7
Diodes Incorporated
-
SMAZ12-13-F
Diodes Incorporated
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