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STMicroelectronics SMBJ30A-TR
- Part No.:
- SMBJ30A-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ30A-TR.pdf
- Description:
- TVS DIODE 30VWM 48.4VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:27,908
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Product details
Overview
SMBJ30A-TR from STMicroelectronics is a unidirectional transient voltage suppression (TVS) diode designed for primary-level surge protection on DC power rails and signal lines. It delivers 600 W peak pulse power (10/1000 µs), clamps transients to 48.4 V at 13 A, and operates up to 150 °C junction temperature-enabling robust protection in industrial power supplies and automotive body electronics.
For engineers reviewing the SMBJ30A-TR datasheet, SMBJ30A-TR pinout, SMBJ30A-TR application, or SMBJ30A-TR equivalent, key selection criteria include standoff voltage (30 V), clamping voltage (48.4 V), low leakage (0.2 µA @ 25 °C), UL497B recognition (E136224), and SMB package compatibility with IPC7531 footprints.
Technical Context
This TVS diode uses planar silicon technology to achieve low leakage current and high thermal stability, supporting reliable operation at Tj = 150 °C. Its unidirectional configuration provides asymmetric clamping-forward conduction only during reverse overvoltage events-making it suitable for DC-biased lines where polarity is fixed.
The device meets IEC 61000-4-2 level 4 (30 kV air/contact discharge) and IEC 61000-4-4 level 4 (4 kV), with dynamic resistance of 0.888 Ω at 10/1000 µs. Its failure mode is short-circuit under overstress, enabling fail-safe detection in protected circuits.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRWM) | 30 V - Maximum continuous DC operating voltage before clamping begins |
| Breakdown Voltage (VBR) | 33.3–35.1 V @ 1 mA - Confirmed avalanche initiation threshold for design margining |
| Clamping Voltage (VCL) | 48.4 V @ 13 A (10/1000 µs) - Actual voltage seen by downstream ICs during surge |
| Peak Pulse Power | 600 W (10/1000 µs), 4 kW (8/20 µs) - Sustained energy-handling capability per waveform standard |
| Leakage Current | 0.2 µA @ 25 °C, 1 µA @ 85 °C - Minimal parasitic loading on sensitive analog or low-power circuits |
| Junction Temperature Range | −55 °C to +150 °C - Enables deployment in under-hood automotive or industrial SMPS environments |
| UL Recognition | UL497B (E136224), IEC 61000-4-2/4-4 compliant - Validated for isolated loop circuit protection per safety standards |
Pinout & Package
The SMBJ30A-TR is housed in an SMB (DO-214AA) surface-mount package measuring 3.30–3.95 mm × 5.10–5.60 mm × 1.90–2.45 mm (L × W × H), with matte tin-plated leads compliant with J-STD-002 and JEDEC registered outline.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Marked Band) | Surge Current Sink | Connected to protected line; conducts transient energy to ground when VREV > VBR |
| Anode | Reference / Ground Return | Typically tied to system ground or low-impedance return path for clamping loop integrity |
Key Features
| Feature | Design Value |
|---|---|
| Planar Silicon Construction | Enables stable VBR tolerance and low leakage across temperature for long-term reliability in SMPS |
| UL497B Recognition (E136224) | Validates suitability as isolated loop protector in telecom and industrial control interfaces |
| Low Dynamic Resistance (0.888 Ω) | Minimizes clamping voltage rise under high-current surges, preserving margin for 3.3 V/5 V logic |
| MSL Level 1 Rating | Allows unlimited floor life and reflow without baking-reducing manufacturing overhead |
| IEC 61000-4-2 Level 4 Compliance | Guarantees survivability against 30 kV ESD events in handheld and field-deployed equipment |
Applications
| Industrial Power Supply Input Protection | Automotive Body Control Module (BCM) CAN Bus Line Protection |
|---|---|
Use Scenario: 24 V DC input rail in programmable logic controllers exposed to load dump and inductive switching transients. IC Role / Device Role / Timing Role: Primary clamping element placed upstream of DC-DC converters and microcontrollers. Use Value: Limits transient voltage to ≤48.4 V, preventing damage to 40 V-rated input stages while maintaining <0.2 µA standby leakage. | Use Scenario: CAN_H line in BCM subjected to ISO 7637-2 pulse 1/2a/5a and ESD events during vehicle assembly. IC Role / Device Role / Timing Role: Unidirectional TVS placed between CAN_H and chassis ground to suppress negative-going transients. Use Value: Clamps 13 A surges within 1 ns, preserving signal integrity and meeting OEM EMC requirements without adding capacitance to the bus. |
| Telecom Remote Power Feeding (RPF) Interface | Smart Meter AC/DC Auxiliary Power Input |
Use Scenario: −48 V DC feeding interface in remote radio units, subject to lightning-induced surges on outdoor cabling. IC Role / Device Role / Timing Role: Standoff-rated TVS on feed line to protect PoE-like DC power management ICs. Use Value: Withstands 600 W pulses and maintains 30 V working voltage-matching telecom nominal supply while surviving 4 kV IEC 61000-4-4 events. | Use Scenario: 12 V auxiliary input derived from rectified AC mains in utility smart meters operating in harsh electrical environments. IC Role / Device Role / Timing Role: First-line transient suppressor before bridge rectifier and linear regulator. Use Value: Operates reliably at 150 °C ambient, ensuring protection continuity during prolonged overtemperature conditions in sealed meter enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ30CA-TR | Bidirectional version; symmetric clamping (±48.4 V); higher capacitance due to dual-junction structure | Required for AC-coupled or bidirectional signal lines (e.g., RS-485, USB D+/D−) | Select only if polarity reversal or AC transients are present; otherwise unidirectional offers lower leakage and capacitance |
| SMBJ33A-TR | Higher standoff (33 V); slightly higher clamping (53.3 V @ 11.8 A); same SMB package and thermal rating | Better margin for 33 V nominal systems; trades clamping tightness for increased working voltage headroom | Choose when system operating voltage approaches 30 V and requires ≥3 V margin above VRWM |
Compared with SMBJ30CA-TR and SMBJ33A-TR, the SMBJ30A-TR provides optimal clamping voltage for 30 V DC systems while minimizing leakage and capacitive loading-critical for high-speed or low-power signal integrity.
Availability
SMBJ30A-TR is available at Aetrix Electronics and suitable for industrial power supplies, automotive body electronics, telecom remote power feeding, and smart meter auxiliary power inputs requiring stable component supply across extended temperature and surge stress conditions.
Supply support for SMBJ30A-TR 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
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, specializing in power management, analog, MEMS, and automotive-grade ICs with strong emphasis on industrial and automotive reliability.
The SMBJ series belongs to ST's transient protection portfolio, engineered specifically for high-energy surge suppression in DC power rails and data lines-balancing clamping performance, thermal robustness, and regulatory compliance for mission-critical applications.
FAQ
What is the maximum clamping voltage of SMBJ30A-TR under a 10/1000 µs surge?
The maximum clamping voltage is 48.4 V at 13 A for a 10/1000 µs waveform, measured at 25 °C ambient. This value increases with junction temperature per the αT coefficient (9.9 × 10−4/°C), reaching approximately 51.2 V at Tj = 125 °C.
Is SMBJ30A-TR suitable for protecting 3.3 V or 5 V logic interfaces?
No-it is not recommended for direct protection of low-voltage logic. With a 30 V standoff and 48.4 V clamping, it is intended for 24 V or higher DC rails. For 3.3 V/5 V interfaces, use lower-voltage TVS devices such as P6SMB5.0A or SMAJ5.0A.
Does SMBJ30A-TR require a heatsink for 600 W pulse handling?
No external heatsink is required for single-pulse 600 W (10/1000 µs) events. The SMB package's thermal impedance (Zth(j-a) ≈ 100 °C/W for short pulses) and 150 °C max junction temperature allow safe dissipation when mounted on a standard FR4 PCB with recommended copper area (≥2 cm² per lead).
How does SMBJ30A-TR differ from SMBJ30CA-TR in circuit layout?
SMBJ30A-TR has polarity-sensitive placement: cathode (banded end) connects to the protected line, anode to ground. SMBJ30CA-TR is bidirectional and symmetrical-no orientation requirement-but introduces ~2× higher junction capacitance, which may degrade high-speed signal integrity in data lines.
SMBJ30A-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AA, SMB
- Series:
- SMBJ, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 30V
- Voltage - Breakdown (Min):
- 33.3V
- Voltage - Clamping (Max) @ Ipp:
- 48.4V
- Current - Peak Pulse (10/1000µs):
- 13A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMB
SMBJ30A-TR FAQ
1.How can I place an order for SMBJ30A-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ30A-TR 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 SMBJ30A-TR reliable?
The price and inventory of SMBJ30A-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ30A-TR is usually 5 days.
3.What payment methods are accepted for SMBJ30A-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ30A-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ30A-TR?
SMBJ30A-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ30A-TR 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 SMBJ30A-TR?
For technical support, including SMBJ30A-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ30A-TR requirements.
6.How does Aetrix verify that SMBJ30A-TR is sourced from the original manufacturer or authorized distributors?
All SMBJ30A-TR 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 SMBJ30A-TR meets industry standards.
7.What is the process for return or replacement of SMBJ30A-TR?
All SMBJ30A-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ30A-TR, 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 SMBJ30A-TR part is unused and in its original packaging.
Return procedure for SMBJ30A-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ30A-TR Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
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D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
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D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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Diodes Incorporated
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