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Taiwan Semiconductor Corporation SMCJ40A
- Part No.:
- SMCJ40A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SMCJ40A.pdf
- Description:
- TVS DIODE 40VWM 64.5VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:6,821
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Product details
Overview
SMCJ40A from Taiwan Semiconductor is a unidirectional 1500W surface-mount transient voltage suppressor (TVS) diode in DO-214AB (SMC) package, with 40V working stand-off voltage (VWM), 44.4–49.1V breakdown voltage (VBR), and 64.5V maximum clamping voltage (VC) at 24A peak pulse current - designed for automotive load-dump and inductive switching protection in power supply rails and DC input stages.
For engineers reviewing the SMCJ40A datasheet, SMCJ40A pinout, SMCJ40A application, or SMCJ40A equivalent, key selection considerations include its 1500W peak pulse power rating, sub-1ps response time, <1μA reverse leakage at 40V, ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance, and unidirectional polarity marking for correct PCB orientation.
Technical Context
The SMCJ40A employs a glass-passivated silicon junction optimized for fast transient suppression in high-energy surge environments. Its clamping behavior is defined by a well-controlled avalanche breakdown mechanism with tight VBR tolerance (±5% typical), enabling predictable overvoltage protection without sacrificing system reliability.
Thermally, it features RθJA = 55°C/W and RθJC = 10°C/W, supporting sustained operation up to TJ = +150°C. The device meets JESD201 Class 2 whisker resistance and J-STD-020 Level 1 moisture sensitivity - confirming suitability for lead-free reflow assembly without preconditioning.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 40 V - Maximum continuous reverse operating voltage before conduction begins; sets safe DC rail margin for 48V systems. |
| VBR @ IT=1mA | 44.4–49.1 V - Breakdown voltage range at 1mA test current; defines precise turn-on threshold for transient detection. |
| VC @ IPPM=24A | 64.5 V - Clamped voltage during 10/1000μs surge; limits downstream IC stress to ≤64.5V under worst-case 1500W event. |
| PPK | 1500 W - Peak pulse power handling per IEC 61000-4-5 and ISO 7637-2; supports automotive-grade load-dump immunity. |
| IR @ VWM | <1 μA - Reverse leakage at rated stand-off voltage; ensures negligible standby current in battery-powered circuits. |
| Response Time | <1.0 ps - Time from 0V to VBR min; enables protection of high-speed logic and analog interfaces against EFT. |
Pinout & Package
Package: DO-214AB (SMC), surface-mount, unidirectional configuration with cathode band marking. Matte tin-plated leads, UL 94V-0 molding compound, 0.210g weight.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or low-impedance return path; forms current sink during clamping. |
| Cathode | High-side transient input terminal | Connected to protected line (e.g., 48V rail); marked with band for polarity verification during placement. |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Enables stable, repeatable avalanche performance across temperature and lifetime; eliminates passivation-related drift in clamping voltage. |
| ISO 7637-2 compliance | Validated for Pulse 1 (inductive switch-off), Pulse 2a/2b (battery disconnect), and Pulse 3a/3b (EFT) - required for automotive ECUs and body controllers. |
| Level 1 moisture sensitivity | Allows direct use from dry pack without baking; reduces manufacturing overhead and avoids moisture-induced popcorning during reflow. |
| RoHS & halogen-free | Meets IEC 61249-2-21 and EU RoHS Directive 2011/65/EU - supports green electronics compliance for global OEMs. |
Applications
| Automotive Power Rail Protection | Industrial PLC Input Protection |
|---|---|
Use Scenario: 48V battery-fed control module exposed to load-dump transients up to 60V during alternator regulation failure. IC Role / Device Role / Timing Role: Unidirectional TVS placed between 48V rail and chassis ground to clamp surges within 1ps and limit voltage to ≤64.5V. Use Value: Prevents damage to PMICs and microcontrollers by absorbing 1500W pulses without degradation, meeting ISO 7637-2 Pulse 5a requirements. |
Use Scenario: 24V DC input stage of programmable logic controller subjected to inductive kickback from solenoid drivers. IC Role / Device Role / Timing Role: Standoff protector on field-side input terminals, conducting only during >44.4V transients while remaining high-impedance at nominal 24V. Use Value: Eliminates need for external series impedance or RC snubbers; <1μA leakage preserves signal integrity in high-impedance sensing circuits. |
| LED Driver Overvoltage Clamp | Telecom DC Feeder Protection |
Use Scenario: Constant-current LED driver board powered from 36V PoE++ source, vulnerable to cable-induced surges. IC Role / Device Role / Timing Role: Primary clamping device across input capacitor, shunting energy before it reaches buck controller and gate drivers. Use Value: 64.5V clamping ensures MOSFETs and current-sense amplifiers remain within absolute maximum ratings during 10/1000μs transients. |
Use Scenario: Central office DC feeder line (−48V) experiencing lightning-induced common-mode spikes on copper pairs. IC Role / Device Role / Timing Role: Unidirectional TVS on each conductor referenced to ground, suppressing differential surges while maintaining -48V bias stability. Use Value: Fast <1ps response captures leading edge of fast-rising transients; DO-214AB thermal mass sustains multiple 1500W events without derating. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ40A (Bourns) | Same DO-214AA (SMB) package; 600W PPK rating (vs. 1500W); VC = 64.5V @ 9.8A. | Limited to lower-energy transients; unsuitable for ISO 7637-2 Pulse 5a or automotive load-dump. | Select only when space-constrained layouts require SMB footprint and surge energy remains ≤600W. |
| 1.5KE40A (ON Semiconductor) | Through-hole DO-201 package; same 40V VWM and 64.5V VC, but 1500W rating achieved with larger thermal mass. | Requires through-hole assembly; incompatible with fully SMT production lines. | Choose for legacy designs or where board-level mechanical robustness outweighs automated placement efficiency. |
Compared with SMBJ40A and 1.5KE40A, the SMCJ40A uniquely delivers 1500W surge capability in a surface-mount DO-214AB package with verified ISO 7637-2 compliance - making it the preferred choice for automotive and industrial SMT power rail protection where both high energy handling and automated manufacturability are required.
Availability
SMCJ40A is available at Aetrix Electronics and suitable for automotive ECUs, industrial PLCs, LED driver modules, and telecom DC feeders requiring stable component supply with full traceability and long-term lifecycle support.
Supply support for SMCJ40A 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
Taiwan Semiconductor Corporation (TSC) is a vertically integrated Taiwanese semiconductor manufacturer specializing in discrete power devices, including TVS diodes, rectifiers, and MOSFETs, with ISO/TS 16949 certification for automotive-grade production.
The SMCJ series was developed specifically for high-reliability transient suppression in automotive and industrial environments - emphasizing robust clamping consistency, AEC-Q101 alignment, and compatibility with lead-free SMT processes.
FAQ
What is the clamping voltage of the SMCJ40A under a standard 10/1000μs surge?
The SMCJ40A exhibits a maximum clamping voltage (VC) of 64.5 V when subjected to a 10/1000μs waveform at 24 A peak pulse current (IPPM). This value is measured per IEC 61000-4-5 and confirmed in Taiwan Semiconductor's official S2104 datasheet - ensuring predictable overvoltage limiting for downstream components such as PMICs and microcontrollers in 48V systems.
Is the SMCJ40A suitable for bidirectional transient protection?
No, the SMCJ40A is a unidirectional TVS diode, indicated by the absence of "C" or "CA" suffix. It conducts only during reverse-biased overvoltage events. For bidirectional protection, the SMCJ40CA variant must be used - which provides symmetrical clamping in both polarities and is explicitly designated for AC-coupled or floating-line applications.
Does the SMCJ40A meet automotive qualification standards?
The SMCJ40A meets ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b requirements for electrical disturbances in road vehicles. While not explicitly AEC-Q101 certified in the public datasheet, its construction - including glass-passivated junction, JESD201 Class 2 whisker resistance, and J-STD-020 Level 1 moisture sensitivity - aligns with automotive process and reliability expectations for TVS diodes.
What is the maximum steady-state power dissipation of the SMCJ40A?
The SMCJ40A has a steady-state power dissipation (PD) rating of 5 W at TA = 25°C. This value applies only to continuous DC or low-frequency reverse-bias conditions - not transient events. In normal operation at 40V VWM, its reverse leakage remains below 1 μA, resulting in negligible static power loss (<40μW).
Can the SMCJ40A be used in place of the SMCJ40 without redesigning the PCB?
Yes - the SMCJ40A and SMCJ40 share identical DO-214AB (SMC) packaging, pinout, and thermal footprint. The "A" suffix denotes tighter VBR tolerance (44.4–49.1 V vs. 44.4–54.3 V for SMCJ40), offering improved clamping predictability without layout changes. Both parts are drop-in compatible for new designs or replacements.
SMCJ40A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AB, SMC
- Series:
- -
- 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:
- 64.5V
- Current - Peak Pulse (10/1000µs):
- 23.3A
- Power - Peak Pulse:
- 1500W (1.5kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AB (SMC)
SMCJ40A FAQ
1.How can I place an order for SMCJ40A through Aetrix?
Please submit a Request for Quotation (RFQ) for SMCJ40A 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 SMCJ40A reliable?
The price and inventory of SMCJ40A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMCJ40A is usually 5 days.
3.What payment methods are accepted for SMCJ40A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMCJ40A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMCJ40A?
SMCJ40A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMCJ40A 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 SMCJ40A?
For technical support, including SMCJ40A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMCJ40A requirements.
6.How does Aetrix verify that SMCJ40A is sourced from the original manufacturer or authorized distributors?
All SMCJ40A 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 SMCJ40A meets industry standards.
7.What is the process for return or replacement of SMCJ40A?
All SMCJ40A units undergo pre-shipment inspection (PSI). If there is an issue with SMCJ40A, 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 SMCJ40A part is unused and in its original packaging.
Return procedure for SMCJ40A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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