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STMicroelectronics SMA6J40A-TR
- Part No.:
- SMA6J40A-TR
- Manufacturer:
- STMicroelectronics
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMA6J40A-TR.pdf
- Description:
- TVS DIODE 40VWM 73.6VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:13,272
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Product details
Overview
SMA6J40A-TR from STMicroelectronics is a unidirectional 600 W transient voltage suppression (TVS) diode designed for primary-level ESD and surge protection in DC power rails and signal lines. It features a 40 V stand-off voltage (VRM), 62.8 V maximum clamping voltage at 9.7 A (10/1000 µs), and operates up to 175 °C junction temperature - enabling robust protection in automotive body electronics, industrial I/O modules, and telecom power supplies.
For engineers reviewing the SMA6J40A-TR datasheet, SMA6J40A-TR pinout, SMA6J40A-TR application, or SMA6J40A-TR equivalent, key selection criteria include clamping performance under 10/1000 µs surges, low leakage (<0.2 µA @ 25 °C), JEDEC DO-214AC (SMA) package compatibility, and IEC 61000-4-2 Level 4 (±30 kV contact/air) compliance.
Technical Context
This TVS diode uses planar silicon technology to achieve stable breakdown characteristics and low dynamic resistance (1.42 Ω typical at 25 °C), ensuring predictable clamping during fast transients. Its unidirectional configuration provides asymmetric protection with low forward voltage drop (≤1.4 V @ 1 A) and high surge current capability (9.7 A peak for 10/1000 µs).
The device meets J-STD-020 MSL Level 1 moisture sensitivity and UL94 V0 flammability requirements, and its thermal design supports sustained operation at Tj = 175 °C - critical for under-hood automotive and high-temperature industrial environments where long-term reliability is mandated.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Stand-off Voltage (VRM) | 40 V - Maximum continuous reverse operating voltage before breakdown; defines minimum system rail margin for reliable blocking. |
| Breakdown Voltage (VBR min) | 44.4 V @ 1 mA - Ensures consistent triggering above nominal rail; guarantees protection activation before downstream IC damage. |
| Clamping Voltage (VCL max) | 62.8 V @ 9.7 A (10/1000 µs) - Limits transient energy delivered to protected circuit; enables safe operation of 48 V systems. |
| Peak Pulse Power (PPP) | 600 W (10/1000 µs) - Sustains standard lightning-surge stress per IEC 61000-4-5; validates use in Class III industrial interfaces. |
| Leakage Current (IRM) | 0.2 µA @ 25 °C - Minimizes standby power loss and avoids false triggering in high-impedance sensor circuits. |
| Junction Temperature Range | –55 °C to +175 °C - Supports deployment in engine control units, motor drives, and outdoor base stations without derating. |
| ESD Withstand (IEC 61000-4-2) | ±30 kV contact & air discharge - Exceeds Level 4 requirement; eliminates need for secondary ESD stages on front-end connectors. |
Pinout & Package
Package: DO-214AC (SMA), JEDEC registered, IPC-7531 compliant footprint, matte tin-plated leads, UL94 V0 resin encapsulation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (marked band) | Surge current sink terminal | Connected to protected line; conducts transient energy to ground when voltage exceeds VRM. |
| Anode | Reference/ground return path | Typically tied to system ground plane; completes low-inductance surge current loop for effective clamping. |
Key Features
| Feature | Design Value |
|---|---|
| Low dynamic resistance | 1.42 Ω - Reduces clamping voltage rise under high-current surges, improving protection margin for 48 V systems. |
| High-temperature operation | 175 °C max Tj - Enables placement near heat sources (e.g., power MOSFETs, inductors) without thermal derating. |
| UL94 V0 flammability rating | Self-extinguishing epoxy - Meets safety standards for enclosed industrial and automotive enclosures. |
| MSL Level 1 handling | No dry-pack or baking required - Simplifies SMT assembly and reduces manufacturing cost in high-volume production. |
Applications
| Automotive Body Control Module (BCM) | Industrial PLC Digital Input Module |
|---|---|
Use Scenario: Protecting 12 V/24 V CAN/LIN bus power rails and switch inputs against load dump and ESD events in vehicle door modules. IC Role / Device Role / Timing Role: Primary overvoltage clamp on supply input; absorbs 600 W surges within 10 µs to prevent MCU reset or LDO latch-up. Use Value: Eliminates need for external series resistors or RC filters while maintaining <0.2 µA leakage to preserve battery life in sleep mode. |
Use Scenario: Safeguarding 24 V digital input channels from field-wiring induced surges and operator ESD in factory automation cabinets. IC Role / Device Role / Timing Role: Front-end transient suppressor on optocoupler input side; clamps to ≤62.8 V within 1 µs to protect isolation barrier integrity. Use Value: Enables direct connection to unshielded field wiring without additional filtering, reducing BOM count and PCB area by 30%. |
| Telecom Power Supply Input | Smart Meter AC/DC Auxiliary Rail |
Use Scenario: Secondary surge protection on 48 V intermediate bus feeding PoE controllers and Ethernet PHYs in network switches. IC Role / Device Role / Timing Role: Fast-response clamp limiting voltage overshoot during hot-swap events and lightning-induced ring waves. Use Value: Maintains <1.42 Ω dynamic resistance across temperature, ensuring consistent clamping performance from –40 °C to +85 °C ambient. |
Use Scenario: Protecting 5 V auxiliary rail derived from mains-connected SMPS against EFT bursts and capacitor discharge transients in utility meters. IC Role / Device Role / Timing Role: Low-leakage (0.2 µA) TVS on microcontroller VDD line; prevents latch-up during 30 kV ESD events per IEC 61000-4-2. Use Value: Achieves full Level 4 ESD immunity without degrading ADC reference stability or RTC accuracy due to minimal leakage drift. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMA6J40AHE3_A/H (Vishay) | Same DO-214AC package; 600 W rating; slightly higher VBR min (45.0 V) and VCL max (64.5 V @ 9.7 A). | Marginally reduced clamping headroom in 48 V systems; requires verification of downstream voltage tolerance. | Preferred for cost-sensitive industrial designs where ±0.5 V clamping variance is acceptable. |
| P6SMB40A (ON Semiconductor) | Identical 40 V VRM and 600 W rating; higher leakage (1.0 µA @ 25 °C); lower Tj max (150 °C). | Not suitable for under-hood automotive or high-ambient industrial use due to thermal limitation. | Select only for commercial-grade applications with ambient <70 °C and no long-term reliability certification required. |
Compared with SMA6J40A-TR, SMA6J40AHE3_A/H offers equivalent surge handling but less clamping precision, while P6SMB40A sacrifices thermal robustness and leakage performance - making the ST device optimal for high-reliability, high-temperature deployments.
Availability
SMA6J40A-TR is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLC I/O protection, and telecom power supply input stages requiring stable component supply, long-lifecycle support, and traceable sourcing.
Supply support for SMA6J40A-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, delivering innovative solutions across automotive, industrial, power, and smart mobility markets.
The SMA6J series belongs to ST's high-reliability TVS portfolio, engineered specifically for demanding ESD/surge protection in automotive ECUs, industrial control systems, and telecom infrastructure where thermal stability and low leakage are critical.
FAQ
What is the maximum clamping voltage of SMA6J40A-TR under a 10/1000 µs surge?
The maximum clamping voltage (VCL) is 62.8 V at 9.7 A for a 10/1000 µs waveform, measured at 25 °C. This value increases with junction temperature at a coefficient of 10.1 × 10⁻⁴/°C, reaching ~65.2 V at Tj = 125 °C per the datasheet's αT correction formula.
Is SMA6J40A-TR suitable for bidirectional signal line protection?
No - SMA6J40A-TR is unidirectional and intended for DC power rail or single-polarity signal protection. For bidirectional applications like USB or RS-485, the SMA6J40CA-TR variant must be used, which provides symmetrical clamping in both polarities.
Does SMA6J40A-TR require special PCB layout considerations?
Yes - ST recommends using the IPC-7531-compliant SMA footprint with ≥1.4 mm pad width and ≥5.4 mm center-to-center spacing. Thermal relief and copper pour under the cathode/anode pads improve heat dissipation and reduce clamping impedance during surge events.
How does the leakage current change with temperature?
Leakage rises exponentially with junction temperature: it is ≤0.2 µA at 25 °C, ≤1 µA at 85 °C, and reaches ~10 µA at 125 °C per Figure 9 in DS5142. This remains well below typical microcontroller input leakage thresholds, preserving system integrity.
SMA6J40A-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:
- 1
- Bidirectional Channels:
- -
- 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)
SMA6J40A-TR FAQ
1.How can I place an order for SMA6J40A-TR through Aetrix?
Please submit a Request for Quotation (RFQ) for SMA6J40A-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 SMA6J40A-TR reliable?
The price and inventory of SMA6J40A-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMA6J40A-TR is usually 5 days.
3.What payment methods are accepted for SMA6J40A-TR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMA6J40A-TR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMA6J40A-TR?
SMA6J40A-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMA6J40A-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 SMA6J40A-TR?
For technical support, including SMA6J40A-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMA6J40A-TR requirements.
6.How does Aetrix verify that SMA6J40A-TR is sourced from the original manufacturer or authorized distributors?
All SMA6J40A-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 SMA6J40A-TR meets industry standards.
7.What is the process for return or replacement of SMA6J40A-TR?
All SMA6J40A-TR units undergo pre-shipment inspection (PSI). If there is an issue with SMA6J40A-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 SMA6J40A-TR part is unused and in its original packaging.
Return procedure for SMA6J40A-TR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMA6J40A-TR Tags
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