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Microchip Technology SMAJ4739CE3/TR13
- Part No.:
- SMAJ4739CE3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ4739CE3/TR13.pdf
- Description:
- DIODE ZENER 9.1V 2W DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:7,963
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Product details
Overview
SMAJ4739CE3/TR13 from SM Semiconductor is a 9.1 V, ±2% tolerance silicon 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 precision voltage regulation and transient overvoltage protection in low-profile power rails and signal lines.
For engineers reviewing the SMAJ4739CE3/TR13 datasheet, SMAJ4739CE3/TR13 pinout, SMAJ4739CE3/TR13 application, or SMAJ4739CE3/TR13 equivalent, key selection criteria include zener voltage tolerance (±2%), thermal resistance (25°C/W), surge current rating (500 A), and ROHS-compliant matte-tin plating for reliable solderability in high-density PCBs.
Technical Context
This device operates as a two-terminal voltage reference and clamping element, with breakdown voltage specified at 9.1 V ±2% under 28 mA test current (IZT). Its 5.0 Ω dynamic impedance at IZT ensures stable regulation across varying load currents.
The SMAJ4739CE3/TR13 features a sharp knee in the reverse breakdown curve verified by dual-point Zener impedance measurement, and maintains regulation over -65°C to +150°C operating temperature range with cathode polarity indicated by a band on the epoxy body.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage (VZ) | 9.1 V ±2% at 28 mA - enables precise voltage reference in feedback loops and clamp thresholds |
| Power Dissipation (PM(AV)) | 2.0 W - supports continuous regulation in compact power supply rails without forced cooling |
| Surge Current (Izsm) | 500 A - withstands 1/2-sine wave transients from inductive switching or ESD events |
| Dynamic Impedance (ZZT) | 5.0 Ω at 28 mA - minimizes output voltage variation under dynamic load changes |
| Reverse Leakage (IR) | 10 µA max at 7.0 V - ensures low standby power loss in always-on protection circuits |
| Thermal Resistance (RθJL) | 25 °C/W junction-to-lead - allows direct thermal path to PCB copper for improved power handling |
| Operating Temperature | -65°C to +150°C - suitable for automotive under-hood and industrial control environments |
Pinout & Package
Package: SMA (DO-214AC), void-free thermosetting epoxy case with cathode band marking; weight ≈0.3 g; ROHS-compliant matte-tin plating per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-side reference node | Connected to ground or lower-potential rail during reverse-bias regulation |
| Cathode | Reverse breakdown terminal / regulated output node | Connected to protected line; voltage clamped to 9.1 V ±2% above anode potential |
Key Features
| Feature | Design Value |
|---|---|
| ±2% Zener voltage tolerance | Enables tighter regulation margins than standard 5% or 10% parts, reducing need for post-regulation trimming |
| 2.0 W steady-state power rating | Supports sustained clamping in 12 V automotive systems without derating below 85°C ambient |
| Sharp knee breakdown characteristic | Verified by dual-point Zener impedance testing, ensuring predictable turn-on and minimal overshoot during transients |
| ROHS-compliant matte-tin plating | Guarantees consistent wetting and intermetallic formation during reflow, critical for high-yield SMT assembly |
Applications
| Automotive Power Rail Protection | Industrial Sensor Signal Clamping |
|---|---|
Use Scenario: Protecting 12 V microcontroller power inputs against load-dump transients up to 35 V in engine control units. IC Role / Device Role / Timing Role: Primary voltage clamp placed between VCC and GND, conducting only during overvoltage events. Use Value: Limits peak rail voltage to ≤9.1 V + dynamic overshoot, preventing latch-up or permanent damage to downstream logic. | Use Scenario: Safeguarding analog outputs of pressure sensors exposed to ESD in factory automation PLC modules. IC Role / Device Role / Timing Role: Bidirectional transient suppressor connected between signal line and ground, leveraging Zener forward conduction below 1.2 V. Use Value: Clamps fast-rising ESD pulses (IEC 61000-4-2 Level 4) while maintaining <10 µA leakage at 7.0 V for signal integrity. |
| Consumer USB Port Overvoltage Guard | Telecom Line Interface Protection |
Use Scenario: Preventing damage to USB 2.0 PHY ICs from hot-plug-induced voltage spikes on VBUS lines. IC Role / Device Role / Timing Role: Standby shunt regulator that activates only when VBUS exceeds 9.1 V, diverting surge current to ground. Use Value: Responds within nanoseconds to 100 ns rise-time transients, limiting excursion to <12 V for <100 ns duration. | Use Scenario: Shielding RS-485 transceivers from lightning-induced surges on long-haul data lines in base station equipment. IC Role / Device Role / Timing Role: Secondary protection stage after gas discharge tube (GDT), absorbing residual energy after primary clamping. Use Value: Handles 500 A 8/20 µs surge current without degradation, maintaining 9.1 V clamping level after repeated strikes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode voltage regulation applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4739A | 10% voltage tolerance (9.1 V ±10%), DO-41 package, 1.0 W rating | Lower power handling and looser tolerance limit use in non-critical bias networks only | Select when cost sensitivity outweighs precision and surge robustness requirements |
| BZX84-C9V1 | ±5% tolerance, SOT-23 package, 300 mW rating, higher ZZT (15 Ω) | Not suitable for >100 mA regulation or high-energy transients due to power and surge limits | Prefer for space-constrained low-power signal conditioning where 500 A surge immunity is unnecessary |
Compared with 1N4739A and BZX84-C9V1, the SMAJ4739CE3/TR13 delivers tighter voltage control, higher surge resilience, and superior thermal performance-making it the preferred choice for automotive and industrial applications demanding reliability under stress.
Availability
SMAJ4739CE3/TR13 is available at Aetrix Electronics and suitable for automotive power rail protection, industrial sensor interface clamping, and telecom line surge suppression requiring stable component supply across extended temperature ranges and high-reliability production cycles.
Supply support for SMAJ4739CE3/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 semiconductors, including Zener diodes, TVS devices, rectifiers, and bridge rectifiers, with ISO 9001-certified production facilities.
The SMAJ47xxA series is designed specifically for high-reliability transient voltage suppression in automotive, industrial, and telecom infrastructure, emphasizing tight tolerance, repeatable surge performance, and ROHS-compliant packaging.
FAQ
What is the Zener voltage tolerance of SMAJ4739CE3/TR13?
The SMAJ4739CE3/TR13 has a Zener voltage tolerance of ±2%, meaning its breakdown voltage is guaranteed between 8.92 V and 9.28 V at 28 mA test current. This tighter tolerance compared to standard 5% or 10% Zeners allows more accurate voltage referencing in feedback networks and reduces design margin overhead. The 'C' suffix in the part number explicitly denotes this 2% grade, confirmed in Table 1 of the official SM Semiconductor datasheet.
Does SMAJ4739CE3/TR13 meet ROHS requirements?
Yes, SMAJ4739CE3/TR13 uses ROHS-compliant annealed matte-tin plating on its terminals, fully compliant with Directive 2011/65/EU. The plating meets MIL-STD-750 Method 2026 for solderability and is applied over copper leads encapsulated in UL94V-0 rated thermosetting epoxy. No lead, cadmium, mercury, hexavalent chromium, PBB, or PBDE substances are present above threshold limits.
What is the maximum surge current rating for SMAJ4739CE3/TR13?
The SMAJ4739CE3/TR13 is rated for a peak surge current (Izsm) of 500 A, measured using a 1/2 sine-wave pulse of 1/120 second duration at 25°C ambient. This value reflects its capability to absorb high-energy transients such as automotive load dump or lightning-induced surges without parametric shift or catastrophic failure, provided adequate PCB copper area is used for heat dissipation.
Can SMAJ4739CE3/TR13 be used in surface-mount designs?
Yes, SMAJ4739CE3/TR13 uses the SMA (DO-214AC) surface-mount package with gull-wing leads compatible with standard reflow profiles. Its 0.3 g mass and ROHS-compliant matte-tin finish ensure reliable wetting and joint formation. The datasheet specifies solderability per MIL-STD-750 Method 2026, and the package footprint aligns with IPC-7351B standard for SMA devices.
How does the thermal resistance of SMAJ4739CE3/TR13 affect its power handling?
The SMAJ4739CE3/TR13 has a junction-to-lead thermal resistance (RθJL) of 25°C/W, enabling effective heat transfer from the die to the PCB copper via the leads. At 100°C case temperature, this allows full 2.0 W power dissipation without exceeding the 150°C maximum junction temperature-critical for sustained operation in enclosed automotive or industrial enclosures where airflow is limited.
SMAJ4739CE3/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:
- ±2%
- 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
SMAJ4739CE3/TR13 FAQ
1.How can I place an order for SMAJ4739CE3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ4739CE3/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 SMAJ4739CE3/TR13 reliable?
The price and inventory of SMAJ4739CE3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ4739CE3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ4739CE3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ4739CE3/TR13 transactions.
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4.How is shipping managed for SMAJ4739CE3/TR13?
SMAJ4739CE3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ4739CE3/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 SMAJ4739CE3/TR13?
For technical support, including SMAJ4739CE3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ4739CE3/TR13 requirements.
6.How does Aetrix verify that SMAJ4739CE3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ4739CE3/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 SMAJ4739CE3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ4739CE3/TR13?
All SMAJ4739CE3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ4739CE3/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 SMAJ4739CE3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ4739CE3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ4739CE3/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
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SMAZ12-13-F
Diodes Incorporated
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