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Microchip Technology SMAJ4739AE3/TR13
- Part No.:
- SMAJ4739AE3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ4739AE3/TR13.pdf
- Description:
- DIODE ZENER 9.1V 2W DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:8,010
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Product details
Overview
SMAJ4739AE3/TR13 from SM Semiconductor is a 9.1 V, 5% tolerance Zener diode in SMA (DO-214AC) package, rated for 2.0 W steady-state power dissipation and 200 mA maximum regulator current at 100°C, used for overvoltage protection of I/O lines and signal paths in industrial sensor interfaces and automotive ECUs.
For engineers reviewing the SMAJ4739AE3/TR13 datasheet, SMAJ4739AE3/TR13 pinout, SMAJ4739AE3/TR13 application, or SMAJ4739AE3/TR13 equivalent, key selection factors include its 9.1 V nominal breakdown voltage, 5% tolerance, 28 mA test current, 5.0 Ω dynamic impedance, and 7.0 V reverse voltage rating at 10 µA leakage.
Technical Context
This Zener diode operates in reverse-biased avalanche mode to clamp transient overvoltages, with a sharp knee at 0.5 mA and specified regulation over 28 mA to 200 mA operating current range. Its thermal resistance of 25 °C/W enables stable voltage reference performance under sustained power dissipation when mounted on adequate copper land.
The device meets UL94V-0 flammability rating via void-free thermosetting epoxy encapsulation and uses ROHS-compliant matte-tin plating for reliable solderability per MIL-STD-750 Method 2026. Cathode polarity is marked by a band on the SMA package body.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage VZ | 9.1 V ±5% at 28 mA - defines clamping threshold for transient suppression |
| Power Dissipation | 2.0 W steady-state - supports continuous regulation without derating up to 100°C junction |
| Dynamic Impedance | 5.0 Ω at 28 mA - ensures low voltage deviation during load transients |
| Reverse Leakage | 10 µA at 7.0 V - guarantees minimal standby current in protected circuits |
| Surge Current | 500 A peak (8/20 µs) - withstands IEC 61000-4-5 Level 4 surges |
| Thermal Resistance | 25 °C/W junction-to-lead - requires ≥25 mm² 1-oz copper pad for full power operation |
Pinout & Package
Package: SMA (DO-214AC), surface-mount, cathode-indicated band, 0.3 g weight, UL94V-0 epoxy body.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal | Connected to lower-potential node; conducts when forward-biased ≤1.2 V at 200 mA |
| Cathode | Avalanche breakdown terminal | Connected to higher-potential node; regulates voltage when reverse-biased above 9.1 V |
Key Features
| Feature | Design Value |
|---|---|
| 5% Zener voltage tolerance | Enables precise clamping within ±0.46 V of 9.1 V target, critical for tight-margin signal line protection |
| 2.0 W power rating | Supports sustained energy absorption in motor drive feedback loops and CAN bus termination networks |
| Low dynamic impedance (5.0 Ω) | Minimizes clamping voltage overshoot during fast-rising ESD events (<1 ns rise time) |
| ROHS-compliant matte-tin plating | Ensures consistent wetting and intermetallic formation during lead-free reflow (260°C peak) |
Applications
| Industrial Sensor Interface | Automotive Body Control Module |
|---|---|
Use Scenario: Protecting analog output lines of pressure/temperature sensors from inductive kickback in PLC cabinets. IC Role / Device Role / Timing Role: Zener clamping element placed between sensor output and ADC input, referenced to ground. Use Value: Limits voltage excursion to ≤9.6 V during 100 V/µs transients, preserving 12-bit ADC accuracy. | Use Scenario: Safeguarding LIN bus transceiver I/O pins against load dump and jump-start surges. IC Role / Device Role / Timing Role: Standby shunt regulator connected between LIN line and chassis ground. Use Value: Clamps 120 V/50 ms load dump pulses to <10 V, preventing transceiver latch-up. |
| Consumer Power Adapter Feedback | Telecom DSL Line Card Protection |
Use Scenario: Stabilizing optocoupler feedback voltage in isolated AC/DC flyback converters. IC Role / Device Role / Timing Role: Precision voltage reference for TL431-based secondary-side regulation. Use Value: Maintains ±1% output regulation across -40°C to +125°C ambient with 28–200 mA bias current. | Use Scenario: Shielding ADSL2+ line driver outputs from lightning-induced surges on outdoor copper pairs. IC Role / Device Role / Timing Role: Primary-stage transient suppressor before transformer coupling to PHY IC. Use Value: Absorbs 150 A (10/700 µs) surges while holding line voltage below 12 V for PHY survival. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4739A | Same 9.1 V/5% spec but in DO-41 axial package; higher RθJA (50 °C/W) limits power handling | Requires through-hole mounting and larger board area; unsuitable for high-density SMT layouts | Select only if legacy through-hole assembly or manual repair is required |
| BZT52-B9V1 | 9.1 V/5% in SOD-123; 500 mW rating, 10x lower surge current (50 A vs. 500 A) | Not suitable for industrial-level surge immunity; limited to low-energy ESD-only scenarios | Choose only for space-constrained consumer electronics with IEC 61000-4-2 compliance only |
Compared with 1N4739A and BZT52-B9V1, SMAJ4739AE3/TR13 delivers superior surge robustness (500 A), SMT compatibility, and thermal performance-making it the preferred choice for automotive and industrial transient suppression where PCB real estate and reliability are critical.
Availability
SMAJ4739AE3/TR13 is available at Aetrix Electronics and suitable for industrial sensor interfaces, automotive body control modules, and telecom line card protection requiring stable component supply and long-term production continuity.
Supply support for SMAJ4739AE3/TR13 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
SM Semiconductor is a Taiwan-based manufacturer specializing in discrete power semiconductors, including Zener diodes, TVS devices, and rectifiers, with ISO 9001-certified production.
The SMAJ47xxA series was designed specifically for high-reliability transient voltage suppression in harsh environments-targeting automotive, industrial automation, and telecom infrastructure applications where robustness and consistency are non-negotiable.
FAQ
What is the exact Zener voltage tolerance for SMAJ4739AE3/TR13?
The SMAJ4739AE3/TR13 has a nominal Zener voltage of 9.1 V with a ±5% tolerance, meaning its actual breakdown voltage falls between 8.65 V and 9.55 V when tested at 28 mA. This tolerance is confirmed in Table 1 of the official SM Semiconductor datasheet (Document Number: SMAJ4728A thru SMAJ4751A), and the "A" suffix in the part number explicitly denotes the 5% grade.
Can SMAJ4739AE3/TR13 be used as a replacement for SMAJ4739A?
Yes, SMAJ4739AE3/TR13 is functionally identical to SMAJ4739A in electrical and thermal specifications. The "E3/TR13" suffix indicates tape-and-reel packaging per EIA-481 standard with ROHS-compliant plating-no electrical or mechanical differences exist. Both share the same 9.1 V Zener voltage, 5% tolerance, and SMA (DO-214AC) package outline.
What is the maximum allowable surge current for SMAJ4739AE3/TR13?
The SMAJ4739AE3/TR13 is rated for a peak surge current (IZSM) of 500 A under an 8/20 µs waveform, as specified in Table 1 of the SM Semiconductor datasheet. This value assumes proper PCB layout with ≥25 mm² of 1-oz copper connected to both terminals to maintain thermal integrity during surge events.
Does SMAJ4739AE3/TR13 meet ROHS requirements?
Yes, SMAJ4739AE3/TR13 complies with ROHS Directive 2011/65/EU. Its terminals feature ROHS-compliant annealed matte-tin plating, verified per MIL-STD-750 Method 2026, and its void-free thermosetting epoxy body meets UL94V-0 flammability standards without halogenated flame retardants.
How does the thermal resistance of SMAJ4739AE3/TR13 affect its power handling?
With a junction-to-lead thermal resistance (RθJL) of 25 °C/W, SMAJ4739AE3/TR13 can dissipate its full 2.0 W rating only when the lead temperature is maintained at ≤100°C. In practice, this requires ≥25 mm² of 1-oz copper connected to each terminal; insufficient copper area causes junction temperature to exceed safe limits and triggers premature thermal failure.
SMAJ4739AE3/TR13 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- DO-214AC, SMA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Voltage - Zener (Nom) (Vz):
- 9.1 V
- Tolerance:
- ±5%
- Power - Max:
- 2 W
- Impedance (Max) (Zzt):
- 5 Ohms
- Current - Reverse Leakage @ Vr:
- 10 µA @ 7 V
- Voltage - Forward (Vf) (Max) @ If:
- 1.2 V @ 200 mA
- Operating Temperature:
- -55°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC
SMAJ4739AE3/TR13 FAQ
1.How can I place an order for SMAJ4739AE3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ4739AE3/TR13 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 SMAJ4739AE3/TR13 reliable?
The price and inventory of SMAJ4739AE3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ4739AE3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ4739AE3/TR13?
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4.How is shipping managed for SMAJ4739AE3/TR13?
SMAJ4739AE3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ4739AE3/TR13 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 SMAJ4739AE3/TR13?
For technical support, including SMAJ4739AE3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ4739AE3/TR13 requirements.
6.How does Aetrix verify that SMAJ4739AE3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ4739AE3/TR13 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 SMAJ4739AE3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ4739AE3/TR13?
All SMAJ4739AE3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ4739AE3/TR13, 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 SMAJ4739AE3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ4739AE3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ4739AE3/TR13 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
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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
-
SMAZ12-13-F
Diodes Incorporated
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