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STMicroelectronics SMBJ12CA-TR
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- Part No.:
- SMBJ12CA-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ12CA-TR.pdf
- Description:
- TVS DIODE 12VWM 19.9VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:3,843
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Product details
Overview
SMBJ12CA-TR from STMicroelectronics is a bidirectional transient voltage suppression (TVS) diode in SMB package, designed for IEC 61000-4-2 ESD protection (30 kV air/contact) and IEC 61000-4-4 surge immunity (4 kV), with 12 V standoff voltage (VRM), 19.9 V clamping voltage at 31 A (10/1000 µs), and 600 W peak pulse power. It protects signal lines and DC power rails in industrial PLCs, telecom interfaces, and automotive body electronics.
For engineers reviewing the SMBJ12CA-TR datasheet, SMBJ12CA-TR pinout, SMBJ12CA-TR application, or SMBJ12CA-TR equivalent, key selection criteria include bidirectional clamping behavior, low leakage (0.2 µA @ 25 °C), high junction temperature rating (150 °C), and UL497B recognition for isolated loop circuits.
Technical Context
This bidirectional TVS diode operates symmetrically across both polarities, enabling robust protection of AC-coupled or floating signal paths without polarity constraints. Its planar silicon junction delivers fast response time (<1 ns) and stable clamping under repetitive transients up to 150 °C junction temperature.
Clamping performance is defined by dynamic resistance (RD = 0.168 Ω at 25 °C), enabling precise VCL prediction via VCL = VCL(25°C) × [1 + αT × (Tj − 25)], where αT = 8.3 × 10⁻⁴/°C. It meets IEC 61000-4-2 Level 4 (30 kV) and IEC 61000-4-4 Level 4 (4 kV), with UL497B recognition (E136224) for isolated loop circuit protection.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 12 V - Maximum continuous reverse operating voltage before significant leakage begins. |
| Breakdown Voltage (VBR min) | 13.3 V @ 1 mA - Guaranteed minimum voltage at which device enters avalanche conduction. |
| Clamping Voltage (VCL) | 19.9 V @ 31 A (10/1000 µs) - Peak voltage seen by protected circuit during worst-case surge. |
| Peak Pulse Power (PPP) | 600 W (10/1000 µs) - Sustained surge energy handling capability at 25 °C ambient. |
| Leakage Current (IRM) | 0.2 µA @ 25 °C, 1 µA @ 85 °C - Minimal DC loading on sensitive analog or reference circuits. |
| Junction Temperature Range | −55 °C to +150 °C - Enables deployment in under-hood automotive or high-temperature industrial enclosures. |
| ESD Rating | 30 kV contact & air discharge (IEC 61000-4-2 Level 4) - Full compliance with end-equipment ESD immunity requirements. |
Pinout & Package
Package: SMB (DO-214AA), surface-mount, JEDEC registered outline, IPC7531 footprint compliant. Dimensions: 3.3–3.95 mm length × 5.1–5.6 mm width × 2.0–2.45 mm height. Matte tin-plated leads, MSL Level 1, solderable per J-STD-020.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (K) | Transient current sink (bidirectional) | Acts as common terminal; conducts surge current equally in either direction when voltage exceeds ±13.3 V. |
| Anode (A) | Transient current sink (bidirectional) | Paired with cathode to form symmetrical clamping path; no polarity dependency in layout placement. |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping symmetry | Enables single-device protection of AC signals, differential buses (e.g., RS-485), or floating sensors without polarity concerns. |
| UL497B recognition (E136224) | Validates suitability for isolated loop circuit protection in industrial instrumentation and process control systems. |
| Low dynamic resistance (0.168 Ω) | Minimizes clamping voltage rise under high-current surges, preserving margin for downstream ICs rated ≤20 V. |
| High-temperature reliability (150 °C Tj max) | Supports operation in thermally constrained environments such as enclosed power supplies or engine-control modules. |
| JEDEC-compliant SMB footprint | Ensures mechanical compatibility with standard automated assembly processes and thermal pad layouts per IPC7531. |
Applications
| Industrial PLC I/O Protection | Automotive Body Control Module |
|---|---|
|
Use Scenario: Protecting 24 V digital input channels against inductive switching transients from solenoids and relays. IC Role / Device Role: Bidirectional TVS clamp placed between input terminal and ground, shunting >1 kV spikes within nanoseconds. Use Value: Prevents latch-up or gate oxide damage in input buffer ICs by limiting transient voltage to ≤19.9 V at 31 A. |
Use Scenario: Safeguarding LIN bus transceivers and microcontroller GPIOs exposed to load-dump and jump-start events. IC Role / Device Role: Secondary-level protection after primary TVS, absorbing residual energy from ISO 7637-2 pulses. Use Value: Maintains signal integrity during 10/1000 µs surges up to 600 W while operating reliably at 125 °C ambient. |
| Telecom Ethernet Interface | Medical Sensor Signal Conditioning |
|
Use Scenario: Shielding RJ45 magnetics secondary side from ESD events during hot-plug connector insertion. IC Role / Device Role: Bidirectional clamping across differential pairs (e.g., TX+/TX−), referenced to local ground plane. Use Value: Withstands 30 kV contact discharge per IEC 61000-4-2 without degradation, ensuring EMC certification pass. |
Use Scenario: Protecting low-noise instrumentation amplifiers connected to piezoresistive or capacitive biosensors. IC Role / Device Role: Low-leakage (0.2 µA) TVS placed at front-end filter stage to avoid DC offset drift or noise injection. Use Value: Preserves sub-microvolt signal fidelity while providing fail-safe clamping during electrostatic handling events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ12CA from Vishay (SMCJ12CA) | Same SMB package, identical VRM (12 V), but higher clamping voltage (21.2 V @ 30 A) and lower PPP (1500 W). | Less effective for tight-clamp designs requiring <20 V VCL; better suited for higher-energy surges where thermal mass dominates. | Select only if system-level testing confirms 21.2 V clamping remains within protected IC's absolute maximum rating. |
| P6SMB12CA from Littelfuse | Identical electrical specs (12 V VRM, 19.9 V VCL @ 31 A), same SMB package, but lacks UL497B recognition and has higher IRM (1 µA @ 25 °C). | Not qualified for isolated loop circuits per UL497B; acceptable for non-safety-critical consumer or computing applications. | Choose when UL certification is not required and cost sensitivity outweighs regulatory compliance needs. |
Compared with SMBJ12CA-TR, the Vishay alternative trades tighter clamping for higher surge capacity, while the Littelfuse part omits UL497B qualification and exhibits higher leakage-making ST's version optimal for safety-critical industrial and automotive signal protection where regulatory alignment and low leakage are mandatory.
Availability
SMBJ12CA-TR is available at Aetrix Electronics and suitable for industrial PLC I/O protection, automotive body control modules, telecom Ethernet interface hardening, and medical sensor signal conditioning requiring stable component supply and full regulatory traceability.
Supply support for SMBJ12CA-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 microcontrollers for industrial, automotive, and consumer markets.
The SMBJ series belongs to ST's Transient Voltage Suppression portfolio, engineered specifically for high-reliability ESD and surge protection in harsh environments where long-term stability, low leakage, and regulatory compliance are critical.
FAQ
What is the difference between SMBJ12CA and SMBJ12A?
SMBJ12CA is bidirectional, providing symmetrical clamping for both positive and negative transients, making it ideal for AC-coupled or floating signal lines. SMBJ12A is unidirectional, clamping only in reverse bias and requiring correct polarity orientation. Their marking differs (BBE vs. BUE), and CA devices show identical VBR/VCL values in both directions per datasheet Table 2.
Does SMBJ12CA-TR meet automotive AEC-Q200 requirements?
No-SMBJ12CA-TR is not AEC-Q200 qualified. It is rated for industrial and general-purpose applications with Tj max = 150 °C and UL497B recognition, but lacks the extended temperature cycling, humidity, and lifetime testing required for automotive qualification. For AEC-Q200, consider ST's Automotive-grade SMAJ or SMCJ series variants.
Can SMBJ12CA-TR be used in parallel for higher surge current handling?
Not recommended without derating analysis. Mismatches in VBR (±5% tolerance) cause current imbalance, leading to premature failure of the lower-VBR device. Parallel use requires matched units, thermal coupling, and verification per Figure 5's IPP vs. VCL curves-ST does not endorse or characterize this configuration in DS1283.
What is the significance of the "-TR" suffix in SMBJ12CA-TR?
The "-TR" suffix denotes tape-and-reel packaging: 2500 units per 13-inch reel, compliant with EIA-481 standards. It specifies delivery format only-not a functional or parametric variant-and matches the marking "BBE" per Table 6. No electrical or thermal differences exist between -TR and bulk versions.
SMBJ12CA-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:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 12V
- Voltage - Breakdown (Min):
- 13.3V
- Voltage - Clamping (Max) @ Ipp:
- 19.9V
- Current - Peak Pulse (10/1000µs):
- 31A
- 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
SMBJ12CA-TR FAQ
1.How can I place an order for SMBJ12CA-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ12CA-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 SMBJ12CA-TR reliable?
The price and inventory of SMBJ12CA-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ12CA-TR is usually 5 days.
3.What payment methods are accepted for SMBJ12CA-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ12CA-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ12CA-TR?
SMBJ12CA-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ12CA-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 SMBJ12CA-TR?
For technical support, including SMBJ12CA-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ12CA-TR requirements.
6.How does Aetrix verify that SMBJ12CA-TR is sourced from the original manufacturer or authorized distributors?
All SMBJ12CA-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 SMBJ12CA-TR meets industry standards.
7.What is the process for return or replacement of SMBJ12CA-TR?
All SMBJ12CA-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ12CA-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 SMBJ12CA-TR part is unused and in its original packaging.
Return procedure for SMBJ12CA-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ12CA-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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Diodes Incorporated
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D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
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D12V0L1B2LP-7B
Diodes Incorporated
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PESD2V0Y1BSFYL
Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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