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Microchip Technology 1N4738PE3/TR12
- Part No.:
- 1N4738PE3/TR12
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-204AL, DO-41, Axial
- Datasheet:
-
1N4738PE3/TR12.pdf
- Description:
- DIODE ZENER 8.2V 1W DO204AL
- Quantity:
- Payment:
- Shipping:
Inventory:8,978
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Product details
Overview
1N4738PE3/TR12 from Microsemi is a 1.0 W, 8.2 V ±5% silicon Zener diode in DO-41 plastic package, rated for 31 mA test current, 4.5 Ω dynamic impedance at IZT, and 6 mA maximum reverse leakage at 6.2 V. It delivers stable voltage regulation in power supply reference and overvoltage protection circuits across -65°C to +150°C.
For engineers reviewing the 1N4738PE3/TR12 datasheet, 1N4738PE3/TR12 pinout, 1N4738PE3/TR12 application, or 1N4738PE3/TR12 equivalent, key selection criteria include Zener voltage tolerance, thermal resistance (45°C/W junction-to-lead), surge current rating (500 mA), RoHS compliance (e3 suffix), and tape-and-reel packaging (TR12).
Technical Context
This device operates in reverse breakdown to maintain a stable 8.2 V reference across a wide current range (0.25–500 mA). Its 45°C/W junction-to-lead thermal resistance enables reliable 1.0 W dissipation at 3/8″ lead length, while its 105°C/W junction-to-ambient rating on FR4 defines PCB layout constraints for thermal management.
The 1N4738PE3/TR12 exhibits a sharp Zener knee with 400 Ω maximum knee impedance at 0.5 mA, supporting low-current regulation stability. Its moisture sensitivity level is IPC/JEDEC J-STD-020B Level 1 - no dry pack required - and it meets MIL-STD-750 Method 1020 for ESD insensitivity.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 8.2 V ±5% at 31 mA - defines precise regulation point for feedback loops and reference rails |
| Power Dissipation | 1.0 W at TL < 105°C - sets maximum continuous DC power under lead-heatsink conditions |
| Dynamic Impedance (ZZT) | 4.5 Ω at 31 mA - determines AC ripple rejection and regulation stiffness under load variation |
| Reverse Leakage (IR) | 10 μA max at 6.2 V - ensures minimal quiescent current in standby or high-impedance bias networks |
| Surge Current (ISM) | 500 mA peak (½-sine, 1/120 s) - supports transient overvoltage clamping without degradation |
| Thermal Resistance | 45°C/W junction-to-lead - requires ≥10 mm lead length from body for full 1.0 W operation |
| Operating Temperature | -65°C to +150°C - validated for industrial, automotive under-hood, and aerospace environments |
Pinout & Package
DO-41 (DO-204AL) plastic axial-leaded package with cathode band marking; void-free UL94V-0 epoxy body, tin-lead or RoHS-compliant matte-tin plating, 0.7 g weight.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Zener cathode reference ground | Connected to circuit ground or lower-potential node; reverse-biased during regulation |
| Cathode | Zener regulation output / voltage reference node | Banded end; connected to regulated rail or error amplifier input; must be held positive relative to anode |
Key Features
| Feature | Design Value |
|---|---|
| JEDEC 1N47xxA registration | Industry-standard footprint and electrical behavior - ensures design reuse and sourcing flexibility |
| RoHS-compliant "e3" suffix | Lead-free matte-tin terminations meeting EU Directive 2011/65/EU and JEDEC J-STD-609A Class 1 |
| Tape-and-reel "TR12" packaging | Standard EIA-296 compliant reel (12,000 pcs/reel) - optimized for automated SMT placement with axial-lead feeders |
| Moisture Sensitivity Level 1 | No dry pack or baking required before assembly - reduces manufacturing overhead and floor-life risk |
| Nonsensitive to ESD | Qualified per MIL-STD-750 Method 1020 - eliminates need for special handling in production environments |
Applications
| Switch-Mode Power Supply Feedback | Industrial Sensor Reference |
|---|---|
Use Scenario: Regulates TL431-type shunt regulator feedback voltage in isolated flyback converters. IC Role / Device Role / Timing Role: Provides stable 8.2 V reference to set output voltage via optocoupler bias network. Use Value: Enables ±1% output accuracy over line/load/temperature with <4.5 Ω dynamic impedance limiting loop gain variation. | Use Scenario: Supplies precision bias voltage to bridge-based pressure transducers in factory automation systems. IC Role / Device Role / Timing Role: Acts as low-drift, low-noise voltage reference for ratiometric ADC excitation. Use Value: Delivers <10 μA leakage at 6.2 V to minimize offset drift in high-impedance sensor interfaces. |
| Overvoltage Clamp Circuit | Microcontroller I/O Protection |
Use Scenario: Clamps 12 V rail transients induced by relay coil switching in PLC backplanes. IC Role / Device Role / Timing Role: Shunts surge energy above 8.2 V to ground using 500 mA peak surge rating. Use Value: Prevents damage to downstream logic with 500 mA non-destructive surge capability and 45°C/W thermal path. | Use Scenario: Protects 3.3 V GPIO pins from accidental 5 V bus coupling in mixed-voltage embedded systems. IC Role / Device Role / Timing Role: Functions as bidirectional clamp between I/O line and 3.3 V rail using forward conduction (<1.2 V @ 200 mA) and Zener action. Use Value: Limits pin voltage to safe levels with 1.2 V forward drop and fast 1/120 s surge response time. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4738A | No "e3" RoHS suffix; Sn/Pb terminations; same electrical specs and DO-41 package | Not suitable for lead-free assembly; requires exemption or waiver for RoHS-compliant production | Select when legacy Pb-based soldering is used and environmental compliance is not required |
| MMSZ4702T1G | Surface-mount SOD-123 package; 8.2 V ±5%; 500 mW rating; 30 mA IZT; higher ZZT (15 Ω) | Lower power handling; unsuitable for 1 W continuous use; requires PCB re-layout | Select only for space-constrained designs where 500 mW derated operation is acceptable |
Compared with 1N4738A and MMSZ4702T1G, the 1N4738PE3/TR12 uniquely combines full 1.0 W dissipation, RoHS compliance, tape-and-reel automation support, and JEDEC-standard axial footprint - making it optimal for high-reliability, volume-manufactured power regulation where thermal robustness and process compatibility are critical.
Availability
1N4738PE3/TR12 is available at Aetrix Electronics and suitable for switch-mode power supplies, industrial sensor references, overvoltage clamp circuits, and microcontroller I/O protection requiring stable component supply and long-term lifecycle assurance.
Supply support for 1N4738PE3/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, RF, and timing solutions for aerospace, defense, and industrial markets.
The 1N47xxAP series was designed specifically for ruggedized voltage regulation in harsh-environment power systems - emphasizing thermal stability, surge resilience, and long-term parametric consistency under extended temperature cycling.
FAQ
What is the Zener voltage tolerance of the 1N4738PE3/TR12?
The 1N4738PE3/TR12 has a nominal Zener voltage of 8.2 V with a ±5% tolerance, as indicated by the "A" suffix in its base part number. This tolerance is verified at 31 mA test current and 25°C lead temperature, ensuring predictable regulation performance in feedback and reference applications.
Does the 1N4738PE3/TR12 require dry packing before PCB assembly?
No, the 1N4738PE3/TR12 is moisture sensitivity level (MSL) 1 per IPC/JEDEC J-STD-020B, meaning it does not absorb sufficient moisture during ambient storage to require dry packing or baking prior to reflow or wave soldering - simplifying manufacturing logistics.
What is the maximum steady-state power dissipation for the 1N4738PE3/TR12?
The 1N4738PE3/TR12 is rated for 1.0 W steady-state power dissipation when lead temperature (TL) is maintained below 105°C at 3/8″ (10 mm) from the body. Derating is required above this temperature, per the published power derating curve in Microsemi's datasheet.
Can the 1N4738PE3/TR12 be used in surface-mount designs?
No - the 1N4738PE3/TR12 uses a DO-41 axial-leaded package and is not surface-mount compatible. For SMT equivalents, consider Microsemi's SMAJ4738A or ON Semiconductor's MMSZ4702T1G, though both differ in power rating, impedance, and thermal performance.
What does the "TR12" suffix indicate in 1N4738PE3/TR12?
"TR12" denotes tape-and-reel packaging per EIA-296 standard, with 12,000 units per reel. This configuration supports automated pick-and-place assembly and is distinct from bulk or ammo-pack options - critical for high-volume production of the 1N4738PE3/TR12.
1N4738PE3/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):
- 8.2 V
- Tolerance:
- ±10%
- Power - Max:
- 1 W
- Impedance (Max) (Zzt):
- 4.5 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 6 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)
1N4738PE3/TR12 FAQ
1.How can I place an order for 1N4738PE3/TR12 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1N4738PE3/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 1N4738PE3/TR12 reliable?
The price and inventory of 1N4738PE3/TR12 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1N4738PE3/TR12 is usually 5 days.
3.What payment methods are accepted for 1N4738PE3/TR12?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1N4738PE3/TR12 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1N4738PE3/TR12?
1N4738PE3/TR12 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1N4738PE3/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 1N4738PE3/TR12?
For technical support, including 1N4738PE3/TR12 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1N4738PE3/TR12 requirements.
6.How does Aetrix verify that 1N4738PE3/TR12 is sourced from the original manufacturer or authorized distributors?
All 1N4738PE3/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 1N4738PE3/TR12 meets industry standards.
7.What is the process for return or replacement of 1N4738PE3/TR12?
All 1N4738PE3/TR12 units undergo pre-shipment inspection (PSI). If there is an issue with 1N4738PE3/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 1N4738PE3/TR12 part is unused and in its original packaging.
Return procedure for 1N4738PE3/TR12:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1N4738PE3/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
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
onsemi
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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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