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Vishay General Semiconductor - Diodes Division SMAJ40AHE3_A/I
- Part No.:
- SMAJ40AHE3_A/I
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ40AHE3_A/I.pdf
- Description:
- TVS DIODE 40VWM 64.5VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:4,838
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Product details
Overview
SMAJ40AHE3_A/I from Vishay General Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in SMA (DO-214AC) package, designed for clamping fast-rising voltage transients on power and signal lines. It features a 40 V stand-off voltage (VWM), 44.4–49.1 V breakdown voltage (VBR) at 1 mA, 64.5 V maximum clamping voltage (VC) at 6.2 A peak pulse current (IPPM), and 400 W peak pulse power rating with 10/1000 μs waveform - used to protect MOSFETs, ICs, and sensor interfaces in automotive and industrial control systems.
For engineers reviewing the SMAJ40AHE3_A/I datasheet, SMAJ40AHE3_A/I pinout, SMAJ40AHE3_A/I application, or SMAJ40AHE3_A/I equivalent, key selection criteria include unidirectional polarity, AEC-Q101 qualification, 150 °C max junction temperature, low incremental surge resistance, and compatibility with automated SMT placement on 0.2" × 0.2" copper pads.
Technical Context
This TVS diode operates as a clamping device that enters avalanche conduction when reverse voltage exceeds its breakdown threshold, limiting transient energy delivered to downstream circuitry. Its glass-passivated junction ensures stable VBR tolerance and long-term reliability under repetitive surge stress.
The SMAJ40AHE3_A/I is rated for 400 W peak pulse power (10/1000 μs), derated to 300 W above 78 V, with thermal resistance of 120 °C/W (junction-to-ambient) and 30 °C/W (junction-to-lead). It meets MSL Level 1 per J-STD-020 and supports lead-free reflow up to 260 °C peak.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 40 V - Maximum continuous reverse operating voltage before clamping begins; defines safe DC/AC working range. |
| VBR min/max | 44.4 V / 49.1 V at 1 mA - Confirmed breakdown range ensures predictable turn-on during overvoltage events. |
| VC @ IPPM | 64.5 V at 6.2 A - Clamping voltage limits stress on protected ICs or MOSFETs during 10/1000 μs transients. |
| PPPM | 400 W (10/1000 μs) - Peak surge energy handling capacity on standard PCB pad layout (0.2" × 0.2"). |
| IFSM | 40 A - Non-repetitive forward surge rating supports robustness against accidental polarity reversal or inrush. |
| TJ max | +150 °C - Enables operation in under-hood automotive and high-temperature industrial environments. |
| Package | SMA (DO-214AC) - Standardized surface-mount outline with cathode band marking; compatible with JEDEC MS-013. |
Pinout & Package
Package: SMA (DO-214AC), molded plastic case with matte tin-plated leads, RoHS-compliant and AEC-Q101 qualified. Cathode indicated by band marking on body; anode is unmarked end.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Transient current sink | Connected to protected line; conducts avalanche current to ground during overvoltage. |
| Anode (unbanded end) | Reference node | Typically tied to system ground or lower-potential rail; completes clamping path. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive electronics use including engine control, ADAS sensors, and infotainment power rails. |
| Glass passivated junction | Ensures stable VBR over time and temperature; reduces parameter drift under repeated surge stress. |
| MSL Level 1 | Unlimited floor life at ≤30 °C/60% RH; supports standard SMT assembly without baking. |
| 400 W peak pulse power | Handles IEC 61000-4-5 Level 4 surges (4 kV/2 Ω) on properly laid out PCBs with 0.2" × 0.2" copper pads. |
| Low clamping ratio (VC/VBR ≈ 1.36) | Minimizes overvoltage overshoot during clamping - critical for protecting 3.3 V or 5 V logic interfaces. |
Applications
| Automotive Power Rail Protection | Industrial Sensor Interface Protection |
|---|---|
Use Scenario: Protecting 12 V supply lines feeding microcontrollers and CAN transceivers in vehicle body control modules. IC Role / Device Role / Timing Role: Unidirectional TVS clamping induced load-dump spikes (ISO 7637-2 Pulse 5a) and alternator transients. Use Value: Limits voltage to ≤64.5 V during 400 W surges, preventing latch-up or gate oxide damage in downstream 3.3 V/5 V ICs. |
Use Scenario: Shielding analog output lines (e.g., 4–20 mA current loops) of pressure/temperature sensors in factory automation PLCs. IC Role / Device Role / Timing Role: Fast-response transient suppressor placed adjacent to connector entry point to absorb ESD and switching noise. Use Value: Sub-1 ns response time and 64.5 V clamping prevent sensor signal corruption and ADC saturation during 8 kV contact ESD events. |
| Consumer Device USB Port Protection | Telecom Line Card Surge Suppression |
Use Scenario: Safeguarding VBUS and D+/D− lines in USB 2.0 host ports of smart home hubs and set-top boxes. IC Role / Device Role / Timing Role: Standoff-rated TVS absorbing IEC 61000-4-2 ESD pulses while maintaining signal integrity below 40 V. Use Value: Low capacitance (<50 pF at 0 V) avoids signal degradation; 40 V VWM allows full USB 2.0 voltage margin. |
Use Scenario: Front-end protection of Ethernet PHY power supplies and data lines in telecom access equipment exposed to lightning-induced surges. IC Role / Device Role / Timing Role: Primary-level unidirectional clamp on 48 V DC bias rails feeding PoE-powered devices. Use Value: 400 W rating handles combination wave surges (10/700 μs); AEC-Q101 qualification ensures long-term field reliability. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ40AE3/61 | Same electrical specs; commercial-grade (non-AEC-Q101), E3 suffix only. | Lacks automotive qualification; suitable for consumer/industrial non-automotive designs. | Select when AEC-Q101 is not required and cost optimization is prioritized. |
| SMAJ43AHE3_A/I | Higher VWM (43 V), VBR (47.8–52.8 V), VC (69.4 V); same package and AEC-Q101 rating. | Better margin for 42 V nominal systems (e.g., dual-battery automotive); trades tighter clamping for higher standoff. | Choose for 42 V battery architectures where 40 V VWM risks leakage or false triggering. |
Compared with SMAJ40AE3/61 and SMAJ43AHE3_A/I, the SMAJ40AHE3_A/I uniquely balances 40 V system compatibility, AEC-Q101 compliance, and 64.5 V clamping - making it optimal for 12 V/24 V automotive ECUs where precise voltage margin and qualification are both mandatory.
Availability
SMAJ40AHE3_A/I is available at Aetrix Electronics and suitable for automotive electronics, industrial sensor interfaces, and telecom power rail protection requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for SMAJ40AHE3_A/I 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
Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, MOSFETs, and protection devices with emphasis on reliability, efficiency, and automotive-grade validation.
The SMAJ series delivers standardized, AEC-Q101-qualified TVS diodes for board-level transient suppression in harsh environments - engineered specifically for automotive, industrial, and telecom infrastructure applications demanding consistent clamping performance.
FAQ
What is the clamping voltage of SMAJ40AHE3_A/I at its rated peak pulse current?
The SMAJ40AHE3_A/I has a maximum clamping voltage (VC) of 64.5 V at 6.2 A peak pulse current (IPPM), measured under the standard 10/1000 μs waveform. This value is confirmed in the Vishay datasheet (Document Number: 88390, Revision: 09-Jan-2024) and defines the upper voltage limit imposed on protected circuits during surge events. The SMAJ40AHE3_A/I maintains this clamping performance across its operational temperature range.
Is SMAJ40AHE3_A/I qualified for automotive applications?
Yes, SMAJ40AHE3_A/I is AEC-Q101 qualified, as explicitly stated in the Vishay ordering information table and mechanical data section. The "HE3" suffix denotes RoHS-compliant and AEC-Q101-qualified construction, validated for use in automotive electronics including engine control units, body modules, and ADAS sensor interfaces. This qualification covers temperature cycling, humidity testing, and surge endurance per AEC standards.
What package type does SMAJ40AHE3_A/I use, and what are its key mounting requirements?
SMAJ40AHE3_A/I uses the SMA (DO-214AC) surface-mount package, with dimensions specified in inches and millimeters in the Vishay datasheet. For optimal thermal and surge performance, it must be mounted on minimum recommended 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal. The device meets MSL Level 1 and supports lead-free reflow up to 260 °C peak, enabling compatibility with standard SMT assembly processes without pre-baking.
How does the breakdown voltage range of SMAJ40AHE3_A/I compare to its stand-off voltage?
The SMAJ40AHE3_A/I has a stand-off voltage (VWM) of 40 V and a breakdown voltage (VBR) range of 44.4 V to 49.1 V at 1 mA test current. This 4.4–9.1 V margin ensures reliable blocking of normal operating voltages while guaranteeing rapid, repeatable avalanche conduction during transients. The VBR tolerance is tightly controlled per ANSI/IEEE C62.35, and the temperature coefficient of VBR is +0.101 %/°C - confirming predictable behavior across temperature.
Can SMAJ40AHE3_A/I be used in bidirectional configurations?
No, SMAJ40AHE3_A/I is a unidirectional TVS diode, as indicated by the "A" suffix (vs. "CA" for bidirectional variants). Its cathode band marking and internal structure support conduction only in reverse bias - forward conduction is limited to 3.5 V at 25 A (per datasheet note). For bidirectional protection, engineers must select an SMAJ40CA variant; mixing unidirectional and bidirectional types in the same design requires careful review of system polarity and grounding topology.
SMAJ40AHE3_A/I Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-214AC, SMA
- Series:
- TransZorb®
- 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):
- 6.2A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
SMAJ40AHE3_A/I FAQ
1.How can I place an order for SMAJ40AHE3_A/I through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ40AHE3_A/I 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 SMAJ40AHE3_A/I reliable?
The price and inventory of SMAJ40AHE3_A/I are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ40AHE3_A/I is usually 5 days.
3.What payment methods are accepted for SMAJ40AHE3_A/I?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ40AHE3_A/I transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ40AHE3_A/I?
SMAJ40AHE3_A/I orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ40AHE3_A/I 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 SMAJ40AHE3_A/I?
For technical support, including SMAJ40AHE3_A/I datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ40AHE3_A/I requirements.
6.How does Aetrix verify that SMAJ40AHE3_A/I is sourced from the original manufacturer or authorized distributors?
All SMAJ40AHE3_A/I 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 SMAJ40AHE3_A/I meets industry standards.
7.What is the process for return or replacement of SMAJ40AHE3_A/I?
All SMAJ40AHE3_A/I units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ40AHE3_A/I, 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 SMAJ40AHE3_A/I part is unused and in its original packaging.
Return procedure for SMAJ40AHE3_A/I:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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