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Microchip Technology SMAJ4737AE3/TR13
- Part No.:
- SMAJ4737AE3/TR13
- Manufacturer:
- Microchip Technology
- Category:
- Single Zener Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ4737AE3/TR13.pdf
- Description:
- DIODE ZENER 7.5V 2W DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:6,658
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Product details
Overview
SMAJ4737AE3/TR13 from SM Semiconductor is a 7.5 V, 5% tolerance Zener diode in SMA (DO-214AC) package, rated for 2.0 W steady-state power dissipation, 34 mA test current, and 242 mA maximum regulator current at 100°C junction temperature, used for precision voltage regulation and transient overvoltage clamping in low-profile power rails.
For engineers reviewing the SMAJ4737AE3/TR13 datasheet, SMAJ4737AE3/TR13 pinout, SMAJ4737AE3/TR13 application, or SMAJ4737AE3/TR13 equivalent, key selection criteria include zener voltage tolerance, surge current capability (605 A), thermal resistance (25 °C/W), cathode-band polarity marking, and ROHS-compliant matte-tin plating for reliable solderability.
Technical Context
This device operates as a silicon planar Zener diode with sharp breakdown knee (IZK = 0.5 mA), specified dynamic impedance of 4.0 Ω at IZT = 34 mA, and reverse leakage current ≤10 µA at VR = 5.0 V. It maintains regulation across -65°C to +150°C operating range with void-free thermosetting epoxy encapsulation meeting UL94V-0.
Designed for unidirectional transient voltage suppression, SMAJ4737AE3/TR13 delivers 2.0 W average power handling and withstands 605 A peak surge current (Izsm) under 1/2-sine 1/120 s pulse conditions, with thermal resistance junction-to-lead fixed at 25 °C/W for lead-mounted thermal management.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Zener Voltage VZ | 7.5 V ±5% at 34 mA - defines precise clamping threshold for 5 V–12 V rail protection |
| Power Dissipation PM(AV) | 2.0 W - supports continuous regulation without forced cooling in compact layouts |
| Dynamic Impedance ZZT | 4.0 Ω at IZT - ensures minimal voltage deviation under load transients |
| Surge Current Izsm | 605 A - handles high-energy inductive switching spikes per 1/120 s pulse standard |
| Thermal Resistance RθJL | 25 °C/W - enables direct lead heat sinking for sustained 242 mA operation at TJ = 100°C |
| Reverse Leakage IR | ≤10 µA at VR = 5.0 V - guarantees low standby power loss in always-on circuits |
| Operating Temperature | -65°C to +150°C - qualified for automotive under-hood and industrial ambient extremes |
Pinout & Package
Package: SMA (DO-214AC), surface-mountable with axial-lead-compatible footprint, void-free UL94V-0 epoxy body, cathode indicated by band, weight ≈0.3 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-side reference node | Connected to circuit ground or lower-potential rail during Zener operation |
| Cathode | Reverse-biased clamping terminal / regulated output node | Marked with band; connects to protected line to clamp transients above 7.5 V |
Key Features
| Feature | Design Value |
|---|---|
| 5% Zener voltage tolerance | Enables tighter regulation than 10% variants (e.g., SMAJ4737) in feedback-sensitive designs |
| ROHS-compliant matte-tin plating | Ensures consistent wetting and intermetallic formation per MIL-STD-750 Method 2026 |
| Sharp knee impedance (IZK = 0.5 mA) | Provides stable turn-on behavior below 1 mA, critical for low-power sensor biasing |
| UL94V-0 epoxy encapsulation | Meets flammability safety requirements for enclosed industrial and automotive enclosures |
| Low-profile SMA package | Reduces board height to ≤2.6 mm, enabling use in space-constrained USB-C PD and IoT modules |
Applications
| Industrial Sensor Signal Conditioning | Automotive Body Control Module (BCM) Power Rail Clamping |
|---|---|
Use Scenario: Protecting analog front-end inputs of 24-bit ADCs in factory-floor pressure/temperature transmitters from ESD and relay-coil flyback. IC Role / Device Role / Timing Role: Zener clamping diode placed between signal line and local 5 V rail to limit excursion to ≤7.5 V. Use Value: Prevents ADC input latch-up and preserves 0.0015% full-scale accuracy by holding common-mode voltage within safe margin. | Use Scenario: Suppressing 12 V battery line transients induced by alternator load dump and solenoid actuation in door-lock control units. IC Role / Device Role / Timing Role: Unidirectional TVS connected anode-to-ground, cathode-to-rail to clamp surges above 7.5 V. Use Value: Withstands 605 A surge pulses while maintaining <10 µA leakage at 5 V, ensuring BCM microcontroller reset immunity. |
| USB-C Power Delivery Adapter Feedback Loop | Telecom DSL Line Interface Protection |
Use Scenario: Stabilizing optocoupler feedback voltage in isolated 65 W USB-C PD adapters operating at 90–264 VAC input. IC Role / Device Role / Timing Role: Precision 7.5 V reference for TL431-like error amplifier biasing in secondary-side regulation. Use Value: 5% tolerance and 4.0 Ω dynamic impedance enable ±0.3% output voltage stability across line/load/temperature. | Use Scenario: Guarding ADSL/VDSL line drivers against lightning-induced surges on twisted-pair copper loops. IC Role / Device Role / Timing Role: Primary-stage clamping element shunting surge energy to ground before reaching integrated line driver IC. Use Value: UL94V-0 epoxy and 25 °C/W RθJL allow mounting directly on telecom PCBs without heatsink, reducing BOM count. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar Zener diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| 1N4737A | Same 7.5 V/5% rating but DO-41 package; higher RθJA (65 °C/W), no ROHS marking | Through-hole assembly only; unsuitable for SMT production or high-density layouts | Select when legacy through-hole design or manual repair is required |
| BZX84-C7V5 | SOT-23 package; 7.5 V/5%, but lower PM(AV) = 300 mW and Izsm = 3 A | Limited to low-energy signal-line protection; cannot replace SMAJ4737AE3/TR13 in power-rail clamping | Choose only for logic-level I/O protection where board space is critical and surge energy is <1 J |
Compared with 1N4737A and BZX84-C7V5, SMAJ4737AE3/TR13 uniquely combines 2.0 W power handling, 605 A surge rating, and SMT-compatible SMA packaging-making it the sole option for automated, high-reliability 12 V rail clamping in automotive and industrial systems.
Availability
SMAJ4737AE3/TR13 is available at Aetrix Electronics and suitable for industrial sensor conditioning, automotive BCM power rail clamping, USB-C PD adapter feedback stabilization, and telecom DSL line interface protection requiring stable component supply across extended temperature ranges and high-volume production cycles.
Supply support for SMAJ4737AE3/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 and global distribution.
The SMAJ47xxA series was designed specifically for high-density, low-profile transient voltage suppression and precision DC voltage regulation in consumer, industrial, and automotive electronics where reliability under thermal and surge stress is critical.
FAQ
What is the Zener voltage tolerance of SMAJ4737AE3/TR13?
SMAJ4737AE3/TR13 has a nominal Zener voltage of 7.5 V with a ±5% tolerance, confirmed in Table 1 of the official SM Semiconductor datasheet (Document Number: SMAJ4728A thru SMAJ4751A). This tighter tolerance versus non-A suffix variants (e.g., SMAJ4737) supports more accurate voltage reference and clamping in feedback-critical applications such as USB-C PD adapters and precision sensor interfaces.
Does SMAJ4737AE3/TR13 meet ROHS compliance requirements?
Yes, SMAJ4737AE3/TR13 uses ROHS-compliant annealed matte-tin plating on its terminals, explicitly stated in the Mechanical Data section of the SM Semiconductor datasheet. This plating ensures solderability per MIL-STD-750 Method 2026 and eliminates lead content, satisfying EU Directive 2011/65/EU and related global environmental regulations without requiring special processing.
What is the maximum surge current rating for SMAJ4737AE3/TR13?
The peak surge current (Izsm) for SMAJ4737AE3/TR13 is 605 A, measured using a 1/2 sine wave pulse of 1/120 second duration at 25°C ambient, as specified in Table 1 of the official datasheet. This rating reflects its capability to absorb high-energy transients from inductive switching and lighting events in automotive and industrial environments.
Can SMAJ4737AE3/TR13 be used as a replacement for SMAJ4737A?
No-SMAJ4737AE3/TR13 and SMAJ4737A differ in packaging and compliance: SMAJ4737AE3/TR13 features ROHS-compliant plating and tape-and-reel packaging (TR13), whereas SMAJ4737A lacks ROHS designation and may ship in bulk or different reel formats. Electrically identical, the "E3" suffix denotes environmental compliance, not functional interchangeability in regulated production.
What is the thermal resistance junction-to-lead for SMAJ4737AE3/TR13?
The thermal resistance junction-to-lead (RθJL) for SMAJ4737AE3/TR13 is 25 °C/W, as published in the Maximum Ratings table of the SM Semiconductor datasheet. This value enables direct heat conduction from the die to PCB copper via the leads, supporting continuous 242 mA regulator current at 100°C junction temperature when mounted with adequate copper pour.
SMAJ4737AE3/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):
- 7.5 V
- Tolerance:
- ±5%
- Power - Max:
- 2 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:
- -55°C ~ 150°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC
SMAJ4737AE3/TR13 FAQ
1.How can I place an order for SMAJ4737AE3/TR13 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ4737AE3/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 SMAJ4737AE3/TR13 reliable?
The price and inventory of SMAJ4737AE3/TR13 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ4737AE3/TR13 is usually 5 days.
3.What payment methods are accepted for SMAJ4737AE3/TR13?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ4737AE3/TR13 transactions.
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4.How is shipping managed for SMAJ4737AE3/TR13?
SMAJ4737AE3/TR13 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ4737AE3/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 SMAJ4737AE3/TR13?
For technical support, including SMAJ4737AE3/TR13 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ4737AE3/TR13 requirements.
6.How does Aetrix verify that SMAJ4737AE3/TR13 is sourced from the original manufacturer or authorized distributors?
All SMAJ4737AE3/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 SMAJ4737AE3/TR13 meets industry standards.
7.What is the process for return or replacement of SMAJ4737AE3/TR13?
All SMAJ4737AE3/TR13 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ4737AE3/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 SMAJ4737AE3/TR13 part is unused and in its original packaging.
Return procedure for SMAJ4737AE3/TR13:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ4737AE3/TR13 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
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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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