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Microchip Technology 1N4737PE3/TR8
- Part No.:
- 1N4737PE3/TR8
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4737PE3/TR8.pdf
- Description:
- DIODE ZENER 7.5V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:8,303
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Product details
Overview
1N4737PE3/TR8 from Microsemi is a 1.0 W axial-lead silicon Zener diode with nominal zener voltage of 7.5 V ±5%, 34 mA test current (IZT), 4.0 Ω dynamic impedance (ZZT) at IZT, and maximum reverse leakage of 5 μA at 6.0 V. It operates from –65°C to +150°C and is used for precision voltage regulation in power supply feedback loops, overvoltage protection circuits, and reference voltage generation.
For engineers reviewing the 1N4737PE3/TR8 datasheet, 1N4737PE3/TR8 pinout, 1N4737PE3/TR8 application, or 1N4737PE3/TR8 equivalent, key selection criteria include its DO-41 package thermal resistance (45°C/W junction-to-lead), RoHS-compliant matte-tin plating, 105°C/W junction-to-ambient rating on FR4, and compliance with MIL-PRF-19500 screening options when prefixed.
Technical Context
This device functions as a two-terminal voltage reference operating in reverse breakdown, delivering stable regulation across 10 mA to 193 mA DC current (IZM = 121 mA at TA = 50°C). Its sharp knee characteristic is verified by dual-point Zener impedance measurement per MicroNote 202, with ZZK = 0.5 Ω at IZK = 5 mA.
The 1N4737PE3/TR8 exhibits a temperature coefficient near zero (≈0 mV/°C) due to its 7.5 V nominal zener voltage - confirmed in Figure 3 of the datasheet - making it suitable for low-drift reference designs where thermal stability is critical.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (Vz) | 7.5 V ±5% at 34 mA - defines regulated output level with tight tolerance for feedback accuracy |
| Power Dissipation | 1.0 W at TL < 105°C (3/8″ lead length) - sets maximum continuous DC power handling before thermal derating |
| Dynamic Impedance (ZZT) | 4.0 Ω at IZT = 34 mA - determines output voltage variation under load transients |
| Max Reverse Leakage | 5 μA at VR = 6.0 V - ensures minimal error current in high-impedance reference paths |
| Junction-to-Lead Rθ | 45°C/W - enables thermal design using lead temperature as proxy for junction temp in PCB layout |
| Operating Temp Range | –65°C to +150°C - supports industrial, automotive under-hood, and military-grade environments |
| Forward Voltage | ≤1.2 V at 200 mA - allows use as clamp or series diode in bidirectional protection schemes |
Pinout & Package
Package: DO-41 (DO-204AL), axial-lead plastic molded epoxy case (UL94V-0), cathode indicated by band. Terminals are tin-lead or RoHS-compliant matte-tin plated, solderable per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Non-banded end | Connected to lower-potential node; forward conduction path when referenced positively |
| Cathode | Banded end | Connected to higher-potential node; reverse-biased terminal during Zener regulation |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC-registered 1N4737A base | Ensures cross-manufacturer compatibility and standardized test conditions per JEDEC JESD24 |
| P-suffix plastic construction | Reduces thermal resistance vs. glass-body (G-suffix) variants - improves power handling in compact layouts |
| e3 RoHS-compliant plating | Meets EU RoHS Directive 2011/65/EU and China RoHS without exemption reporting burden |
| Moisture Sensitivity Level 1 | Eliminates dry-pack requirement and floor-life constraints - simplifies SMT and manual assembly logistics |
| ESD robustness | Nonsensitive per MIL-STD-750 Method 1020 - withstands handling without special ESD controls |
Applications
| Switching Power Supply Feedback | Overvoltage Clamp Circuit |
|---|---|
Use Scenario: Regulates output voltage in flyback or buck converter feedback networks via optocoupler-coupled error amplifier. IC Role / Device Role / Timing Role: Precision voltage reference establishing feedback threshold for PWM controller. Use Value: 7.5 V ±5% tolerance and 4.0 Ω dynamic impedance minimize output deviation across line/load/temperature. |
Use Scenario: Protects downstream ICs from transient overvoltage events on 5 V or 12 V rails. IC Role / Device Role / Timing Role: Shunt clamping element diverting excess energy to ground during surge. Use Value: 1.0 W power rating and 121 mA max regulator current sustain 8/20 μs surges up to 700 mA peak. |
| Fixed Reference Voltage Source | Current-Limited Bias Generator |
Use Scenario: Provides stable bias for op-amp comparators or ADC reference buffers in sensor signal chains. IC Role / Device Role / Timing Role: Two-terminal passive reference replacing active voltage references where cost and simplicity dominate. Use Value: Near-zero temperature coefficient at 7.5 V reduces drift to <±0.5 mV/°C over –40°C to +85°C. |
Use Scenario: Generates fixed bias current for discrete transistor amplifiers or LED drivers using series resistor. IC Role / Device Role / Timing Role: Stable voltage node enabling predictable current setpoint via Ohm's Law. Use Value: Low ZZT (4.0 Ω) maintains regulation accuracy even with ±10% resistor tolerance and ambient temp shifts. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4737A (Microsemi, non-e3, non-TR) | Same electrical specs but Sn/Pb plating and bulk packaging - not RoHS-compliant or tape-and-reel ready | Acceptable for legacy industrial designs without RoHS or automated assembly requirements | Select only if RoHS compliance and TR8 reel format are not required |
| BZX55-C7V5 (Vishay) | Same 7.5 V ±5%, 1 W rating, DO-35 package - higher thermal resistance (65°C/W) and no MIL screening option | Suitable for cost-sensitive consumer electronics where military screening and low Rθ are unnecessary | Prefer for high-volume commercial boards where DO-35 footprint fits existing layout |
Compared with 1N4737PE3/TR8, the 1N4737A lacks RoHS compliance and reel packaging, limiting modern production use; BZX55-C7V5 offers identical regulation but inferior thermal performance and no extended screening path, reducing suitability for harsh-environment designs.
Availability
1N4737PE3/TR8 is available at Aetrix Electronics and suitable for switching power supplies, overvoltage protection circuits, and precision reference voltage generation requiring stable component supply across industrial, aerospace, and medical OEM programs.
Supply support for 1N4737PE3/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 radiation-hardened components for defense, aerospace, and industrial markets.
The 1N4737PE3/TR8 belongs to Microsemi's legacy 1N47xxAP Zener series - engineered for stable voltage regulation in mission-critical power systems where long-term parametric consistency and MIL-qualified screening options are essential.
FAQ
What is the zener voltage tolerance for 1N4737PE3/TR8?
The 1N4737PE3/TR8 has a nominal zener voltage of 7.5 V with a tolerance of ±5%, as indicated by the "A" suffix in its base part number 1N4737A. This tolerance is measured at 34 mA test current and 25°C lead temperature, per JEDEC JESD24 standards documented in the Microsemi datasheet.
Does 1N4737PE3/TR8 support military-grade screening?
Yes - the base 1N4737A is qualified under MIL-PRF-19500, and military screening levels (JAN, JANTX, JANTXV, JANS) can be obtained by adding MQ, MX, MV, or MSP prefixes respectively. The 1N4737PE3/TR8 itself is commercial-grade but shares the same die and construction as screened variants.
What does the "e3" and "TR8" suffix mean in 1N4737PE3/TR8?
The "e3" suffix denotes RoHS-compliant matte-tin plating per JEDEC J-STD-609, and "TR8" indicates tape-and-reel packaging per EIA-296 standard with 8 mm carrier tape - enabling automated pick-and-place assembly. The "P" confirms plastic DO-41 packaging, distinguishing it from glass-body (G-suffix) versions.
Can 1N4737PE3/TR8 replace 1N4737A in existing designs?
Yes - the 1N4737PE3/TR8 is a direct functional and mechanical replacement for 1N4737A, with identical electrical specifications, DO-41 package dimensions, and polarity marking. The only differences are RoHS-compliant plating and tape-and-reel packaging, both backward-compatible with legacy footprints and assembly processes.
What is the maximum steady-state current for 1N4737PE3/TR8 at 50°C ambient?
At TA = 50°C, the maximum regulator current (IZM) for 1N4737PE3/TR8 is 121 mA, derived from its 1.0 W power rating and thermal derating curve. This value assumes mounting on FR4 with 1 oz copper, 4 mm² pads, and 1 mm × 25 mm trace - per the datasheet's thermal resistance specification of 105°C/W junction-to-ambient.
1N4737PE3/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):
- 7.5 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 4 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 5 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)
1N4737PE3/TR8 FAQ
1.How can I place an order for 1N4737PE3/TR8 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4737PE3/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 1N4737PE3/TR8 reliable?
The price and inventory of 1N4737PE3/TR8 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4737PE3/TR8 is usually 5 days.
3.What payment methods are accepted for 1N4737PE3/TR8?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4737PE3/TR8 transactions.
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4.How is shipping managed for 1N4737PE3/TR8?
1N4737PE3/TR8 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4737PE3/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 1N4737PE3/TR8?
For technical support, including 1N4737PE3/TR8 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4737PE3/TR8 requirements.
6.How does Aetrix verify that 1N4737PE3/TR8 is sourced from the original manufacturer or authorized distributors?
All 1N4737PE3/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 1N4737PE3/TR8 meets industry standards.
7.What is the process for return or replacement of 1N4737PE3/TR8?
All 1N4737PE3/TR8 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4737PE3/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 1N4737PE3/TR8 part is unused and in its original packaging.
Return procedure for 1N4737PE3/TR8:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4737PE3/TR8 Tags
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Diodes Incorporated
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