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STMicroelectronics SMA6J40CA-TR
- Part No.:
- SMA6J40CA-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMA6J40CA-TR.pdf
- Description:
- TVS DIODE 40VWM 73.6VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:14,631
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Product details
Overview
SMA6J40CA-TR from STMicroelectronics is a bidirectional 40 V standoff transient voltage suppression (TVS) diode in SMA package, rated for 600 W peak pulse power (10/1000 µs), 4 kV IEC 61000-4-4 level 4 surge immunity, and 30 kV ESD protection (IEC 61000-4-2, air/contact discharge). It clamps to 62.8 V at 9.7 A, features 0.2 µA leakage at 25 °C, and operates up to +175 °C junction temperature - deployed in industrial power supply input stages and automotive body control modules.
For engineers reviewing the SMA6J40CA-TR datasheet, SMA6J40CA-TR pinout, SMA6J40CA-TR application, or SMA6J40CA-TR equivalent, key selection criteria include bidirectional clamping behavior, low dynamic resistance (1.42 Ω), high-temperature reliability, and IPC7531-compliant SMA footprint compatibility with FR4 PCB thermal management.
Technical Context
This TVS diode uses planar silicon technology to achieve stable breakdown voltage (44.4–49.1 V), low leakage (<1 µA at 85 °C), and robust surge handling across both polarities. Its bidirectional architecture enables symmetric clamping without polarity dependency, critical for AC-coupled signal lines and ungrounded bus protection.
The device complies with JEDEC DO-214AC (SMA) mechanical outline and meets J-STD-020 MSL Level 1, UL94 V0 resin, and MIL-STD-750 solderability standards. Thermal impedance is optimized for 70 µm Cu FR4 boards, supporting sustained operation at Tj = 175 °C under repetitive transients.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRM) | 40 V - Maximum continuous reverse operating voltage before conduction begins |
| Breakdown Voltage (VBR) | 44.4–49.1 V at 1 mA - Ensures reliable triggering margin above system nominal voltage |
| Clamping Voltage (VCL) | 62.8 V at 9.7 A (10/1000 µs) - Limits downstream voltage stress during surge events |
| Peak Pulse Power | 600 W (10/1000 µs) - Sustains industrial-grade lightning-induced surges per IEC 61000-4-5 |
| Leakage Current | 0.2 µA at 25 °C - Minimizes standby power loss in battery-backed circuits |
| Junction Temperature Range | −55 to +175 °C - Enables deployment in under-hood automotive and industrial motor drive environments |
| ESD Rating | ±30 kV contact/air discharge (IEC 61000-4-2) - Exceeds Level 4 for robust human-body-model immunity |
Pinout & Package
Package: SMA (DO-214AC), JEDEC registered, UL94 V0 compliant epoxy case, matte tin-plated leads, IPC7531 footprint compatible.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (K) | Reverse-biased terminal for unidirectional mode; symmetrical node in bidirectional configuration | In SMA6J40CA-TR, both terminals are functionally identical - no polarity marking required for AC protection |
| Anode (A) | Forward-biased terminal for unidirectional mode; symmetrical node in bidirectional configuration | Terminal symmetry enables placement flexibility on differential or floating lines without orientation constraints |
Key Features
| Feature | Design Value |
|---|---|
| Bidirectional clamping | Enables single-device protection of AC signals, RS-485 buses, and ungrounded DC links without polarity concerns |
| Low dynamic resistance (RD) | 1.42 Ω - Reduces clamping voltage rise under high-current surges, improving protection margin |
| High-temperature operation | 175 °C max Tj - Supports long-term reliability in thermally constrained enclosures near power converters |
| UL94 V0 resin housing | Prevents flame propagation during catastrophic failure, meeting industrial safety compliance requirements |
| MSL Level 1 rating | Allows unlimited floor life and reflow without dry-packaging - simplifies SMT assembly logistics |
Applications
| Industrial Power Input Protection | Automotive Body Control Module (BCM) |
|---|---|
|
Use Scenario: 24 V DC input stage of programmable logic controllers exposed to load dump and ISO 7637-2 pulses. IC Role / Device Role / Timing Role: Primary overvoltage clamp limiting transient energy entering DC-DC converters and microcontrollers. Use Value: Clamps to 62.8 V within nanoseconds, preventing damage to 36 V-rated downstream regulators and ensuring >100,000 surge cycles per IEC 61000-4-5. |
Use Scenario: CAN FD data lines and LIN bus interfaces in vehicle door modules subject to ESD and battery reversal. IC Role / Device Role / Timing Role: Bidirectional ESD suppressor placed directly at connector entry point, before signal conditioning ICs. Use Value: Withstands ±30 kV contact discharge and clamps <100 ns, preserving signal integrity while protecting PHY transceivers rated for 40 V abs max. |
| RS-485 Communication Port | Smart Energy Meter Interface |
|
Use Scenario: Differential A/B lines of industrial RS-485 transceivers connected to long cable runs in factory automation. IC Role / Device Role / Timing Role: Common-mode surge limiter between twisted pair and transceiver, referenced to local ground. Use Value: Symmetric 62.8 V clamping ensures balanced line protection without skew, maintaining common-mode rejection ratio (CMRR) >60 dB up to 1 MHz. |
Use Scenario: M-Bus (EN 13757-2) current loop interface in utility meters installed in outdoor cabinets. IC Role / Device Role / Timing Role: Secondary protection element after gas discharge tube (GDT), absorbing residual fast-rising transients. Use Value: Low leakage (0.2 µA) avoids metering accuracy drift; 175 °C rating supports operation in sealed enclosures reaching 85 °C ambient. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar bidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMA6J40A-TR | Unidirectional version; same VBR/VCL but conducts only in reverse direction | Requires explicit polarity alignment; unsuitable for AC or floating differential lines | Select only when circuit ground reference is fixed and forward conduction must be blocked |
| SMBJ40CA | Same 40 V VRM and bidirectional function, but SMB package (higher 600 W rating, larger footprint) | Offers lower thermal resistance (Rth(j-a) ≈ 50 °C/W vs. SMA's ~75 °C/W) for higher average power dissipation | Choose when board space allows and thermal cycling exceeds 1000 cycles/hour in high-reliability systems |
Compared with SMA6J40A-TR, SMA6J40CA-TR provides polarity-agnostic protection essential for differential signaling; versus SMBJ40CA, it trades thermal performance for compactness - optimal for space-constrained industrial gateways and automotive ECUs.
Availability
SMA6J40CA-TR is available at Aetrix Electronics and suitable for industrial power input protection, automotive body control modules, RS-485 communication ports, and smart energy meter interfaces requiring stable component supply across extended temperature and surge environments.
Supply support for SMA6J40CA-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, designing and manufacturing analog, power, MCU, and sensor solutions for industrial, automotive, and consumer markets.
SMA6JxxCA belongs to ST's high-reliability TVS diode portfolio targeting harsh-environment surge protection, with emphasis on automotive-grade thermal stability, ESD robustness, and JEDEC-compliant manufacturability.
FAQ
What is the maximum clamping voltage of SMA6J40CA-TR under a 10/1000 µs surge?
The maximum clamping voltage is 62.8 V at 9.7 A for a 10/1000 µs waveform, measured at Tamb = 25 °C. This value increases linearly with junction temperature due to the αT coefficient of 10⁻⁴/°C, reaching approximately 65.2 V at Tj = 125 °C per the datasheet's derating formula.
Can SMA6J40CA-TR replace SMA6J40A-TR in an existing design?
No - SMA6J40CA-TR is bidirectional while SMA6J40A-TR is unidirectional. Substitution requires verifying that the protected circuit has no DC bias across the TVS and that both polarities of transient events must be suppressed. Incorrect replacement may cause forward conduction and latch-up in grounded systems.
Does SMA6J40CA-TR meet automotive qualification standards?
While not AEC-Q200 qualified, SMA6J40CA-TR meets critical automotive-relevant specs: 175 °C Tj(max), ±30 kV ESD, 4 kV EFT (IEC 61000-4-4), and MSL Level 1. It is widely used in non-safety-critical BCM and infotainment interfaces where full AEC-Q200 is not mandated.
What is the recommended PCB footprint for SMA6J40CA-TR?
The manufacturer specifies an IPC7531-compliant SMA footprint: pad length 2.63 mm (0.104"), pad width 1.40 mm (0.055"), center-to-center spacing 5.43 mm (0.214"). Copper area ≥1.64 cm² per lead is advised to maintain Rth(j-a) ≤ 75 °C/W and prevent thermal runaway during repetitive surges.
SMA6J40CA-TR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Package/Case:
- DO-214AC, SMA
- Series:
- SMA6J, TRANSIL™
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 40V
- Voltage - Breakdown (Min):
- 44.4V
- Voltage - Clamping (Max) @ Ipp:
- 73.6V
- Current - Peak Pulse (10/1000µs):
- 48A (8/20µs)
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
SMA6J40CA-TR FAQ
1.How can I place an order for SMA6J40CA-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMA6J40CA-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 SMA6J40CA-TR reliable?
The price and inventory of SMA6J40CA-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMA6J40CA-TR is usually 5 days.
3.What payment methods are accepted for SMA6J40CA-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMA6J40CA-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMA6J40CA-TR?
SMA6J40CA-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMA6J40CA-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 SMA6J40CA-TR?
For technical support, including SMA6J40CA-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMA6J40CA-TR requirements.
6.How does Aetrix verify that SMA6J40CA-TR is sourced from the original manufacturer or authorized distributors?
All SMA6J40CA-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 SMA6J40CA-TR meets industry standards.
7.What is the process for return or replacement of SMA6J40CA-TR?
All SMA6J40CA-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMA6J40CA-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 SMA6J40CA-TR part is unused and in its original packaging.
Return procedure for SMA6J40CA-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMA6J40CA-TR Tags
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