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Vishay General Semiconductor - Diodes Division SMB8J40CAHM3_B/I
- Part No.:
- SMB8J40CAHM3_B/I
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMB8J40CAHM3_B/I.pdf
- Description:
- 800W,40V 5%,BIDIR,SMB TVS
- Quantity:
- Payment:
- Shipping:
Inventory:7,104
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Product details
Overview
SMB8J40CAHM3_B/I from Vishay General Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in SMB (DO-214AA) package, designed for high-energy surge protection on power and signal lines. It features a 40 V stand-off voltage (VWM), 44.4–49.1 V breakdown voltage (VBR), 64.5 V clamping voltage (VC) at 12.4 A peak pulse current (IPPM), and 800 W peak pulse power (PPPM) with 10/1000 µs waveform - suitable for automotive-grade ESD and load-dump protection in engine control units and body electronics.
For engineers reviewing the SMB8J40CAHM3_B/I datasheet, SMB8J40CAHM3_B/I pinout, SMB8J40CAHM3_B/I application, or SMB8J40CAHM3_B/I equivalent, this device delivers AEC-Q101-qualified robustness, low incremental surge resistance, and MSL Level 1 moisture sensitivity - critical for under-hood automotive designs requiring long-term reliability under thermal cycling and repetitive transients.
Technical Context
This bidirectional TVS operates symmetrically across both polarities, enabling protection of AC-coupled or differential signal paths without polarity constraints. Its glass-passivated junction ensures stable VBR tolerance and low leakage (<1.0 µA at VWM), while the low RθJL (20 °C/W) supports sustained surge handling when mounted on recommended 5.0 mm × 5.0 mm copper pads.
The device complies with ANSI/IEEE C62.35 for transient suppression and meets AEC-Q101 stress test requirements including temperature cycling, humidity bias, and mechanical shock - confirming suitability for automotive powertrain and chassis modules where failure modes must be mitigated to ISO 7637-2 Pulse 1/2a/5a levels.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 40 V - maximum continuous reverse operating voltage before clamping begins; defines safe operating margin below system rail. |
| VBR (min/max) | 44.4 V / 49.1 V at 1.0 mA - tight breakdown window ensures predictable turn-on during transients without premature conduction. |
| VC @ IPPM | 64.5 V at 12.4 A (10/1000 µs) - clamping voltage limits downstream IC stress to safe levels during ISO 7637-2 Pulse 5a events. |
| PPPM | 800 W - peak surge energy absorption capacity; enables protection against 12 V automotive load-dump surges up to 35 V/100 ms. |
| ID @ VWM | <1.0 µA - ultra-low leakage preserves battery life in always-on vehicle networks (e.g., CAN/LIN standby nodes). |
| TJ max | +150 °C - extended junction temperature rating supports placement near heat sources in power distribution modules. |
| Package | SMB (DO-214AA) - surface-mount footprint compatible with automated assembly; 2.20 mm × 3.94 mm × 1.95 mm body with matte tin leads. |
Pinout & Package
Package: SMB (DO-214AA), bi-directional configuration with no polarity marking; symmetrical terminals for AC-coupled protection.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Transient current path | Both terminals serve identical roles; bidirectional conduction allows placement across any two points needing clamping regardless of DC bias direction. |
| Cathode Band (absent) | Polarity indicator | Not present - confirms bidirectional functionality; eliminates risk of incorrect orientation during placement. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive applications including engine control, ADAS sensors, and infotainment power rails per stress test requirements. |
| Halogen-free & RoHS-compliant (HM3 suffix) | Meets EU Directive 2011/65/EU and JESD201 Class 2 whisker resistance; supports sustainable manufacturing and end-of-life compliance. |
| MSL Level 1 (260 °C peak reflow) | Enables single-pass lead-free reflow soldering without pre-baking; reduces production complexity and cost in high-volume automotive PCB assembly. |
| Low RθJL = 20 °C/W | Enhances thermal dissipation during repetitive surge events, extending device lifetime in cyclic load-dump environments like alternator regulation circuits. |
| Glass-passivated junction | Provides stable VBR over time and temperature, minimizing parameter drift in under-hood applications subject to thermal aging. |
Applications
| Automotive Engine Control Unit (ECU) | Industrial PLC I/O Module |
|---|---|
Use Scenario: Protection of 12 V supply input against ISO 7637-2 Pulse 5a (load dump) transients up to 60 V/400 ms. IC Role / Device Role / Timing Role: Primary clamping element placed upstream of DC-DC converter input stage. Use Value: Limits voltage seen by downstream regulator to ≤64.5 V, preventing overvoltage shutdown or latch-up during alternator field collapse. |
Use Scenario: Surge protection on 24 V digital input channels exposed to inductive switching noise from solenoids and contactors. IC Role / Device Role / Timing Role: Bidirectional shunt clamp on isolated optocoupler input side. Use Value: Clamps ±1 kV EFT bursts (IEC 61000-4-4) to <65 V, preserving signal integrity and preventing false triggering of logic inputs. |
| Automotive Body Control Module (BCM) | Telecom Power Interface |
Use Scenario: Protection of LIN bus transceiver power pins against battery reversal and jump-start surges. IC Role / Device Role / Timing Role: Secondary overvoltage clamp parallel to primary TVS, sharing surge current. Use Value: Withstands 100 A non-repetitive forward surge (IFSM), enabling robustness during 24 V jump-start conditions without degradation. |
Use Scenario: DC feed protection in PoE-powered remote radio units subjected to lightning-induced surges on outdoor cabling. IC Role / Device Role / Timing Role: First-stage clamping on 48 V DC input before active DC-DC conversion. Use Value: Absorbs 800 W peak pulse energy (10/1000 µs), reducing stress on downstream MOVs and enabling smaller secondary protection stages. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMB8J40CAHE3_B/I | Same electrical specs, but RoHS-compliant commercial grade (non-halogen-free); lacks JESD201 Class 2 whisker resistance. | Approved for industrial/commercial use only; not certified for automotive under AEC-Q101. | Select when halogen-free requirement is absent and cost optimization is prioritized over automotive qualification. |
| SMAJ40CA | Lower PPPM (400 W), higher VC (69.4 V), SMA package (smaller thermal mass, higher RθJA = 110 °C/W). | Limited to lower-energy transients; unsuitable for automotive load-dump duty cycles requiring >500 W sustained absorption. | Choose only for space-constrained consumer electronics where 400 W surge rating suffices and AEC-Q101 is not required. |
Compared with SMB8J40CAHM3_B/I, the HE3 variant omits halogen-free compliance and AEC-Q101 validation, while the SMAJ40CA sacrifices 50 % peak power handling and thermal performance - making SMB8J40CAHM3_B/I the sole option meeting full automotive-grade surge, thermal, and material compliance requirements.
Availability
SMB8J40CAHM3_B/I is available at Aetrix Electronics and suitable for automotive electronics, industrial control systems, and telecom power interfaces requiring stable component supply with guaranteed AEC-Q101 qualification and halogen-free compliance.
Supply support for SMB8J40CAHM3_B/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 high-reliability diodes, MOSFETs, and passive components for automotive, industrial, and computing markets.
The SMB8JxxCA series targets AEC-Q101-compliant transient suppression in harsh-environment automotive subsystems - engineered for consistent clamping performance across -55 °C to +150 °C and validated for long-term operation under thermal cycling and humidity bias.
FAQ
What is the clamping voltage of SMB8J40CAHM3_B/I at its rated peak pulse current?
The SMB8J40CAHM3_B/I has a maximum clamping voltage (VC) of 64.5 V at 12.4 A peak pulse current (IPPM) under the standard 10/1000 µs waveform. This value is measured per ANSI/IEEE C62.35 and ensures downstream circuitry remains within safe operating limits during automotive load-dump events. The SMB8J40CAHM3_B/I maintains this clamping performance across its full operating temperature range (-55 °C to +150 °C).
Is SMB8J40CAHM3_B/I suitable for bidirectional signal line protection?
Yes, SMB8J40CAHM3_B/I is explicitly designed as a bidirectional TVS diode, with symmetrical breakdown characteristics in both polarities. Its datasheet specifies matched VBR min/max values (44.4 V / 49.1 V) and identical clamping behavior for positive and negative transients - making it ideal for protecting differential buses like RS-485, CAN FD, or analog sensor pairs where polarity cannot be assumed. The SMB8J40CAHM3_B/I requires no orientation during placement due to absence of cathode band marking.
Does SMB8J40CAHM3_B/I meet automotive qualification standards?
Yes, SMB8J40CAHM3_B/I is AEC-Q101 qualified and carries the HM3 suffix denoting halogen-free, RoHS-compliant, and automotive-grade construction. It passes all required stress tests including temperature cycling, high-temperature reverse bias, and mechanical shock - documented in Vishay's qualification report referenced in datasheet 88422. This certification validates SMB8J40CAHM3_B/I for use in engine control, transmission, and ADAS modules where functional safety and long-term reliability are mandatory.
What is the thermal resistance profile of SMB8J40CAHM3_B/I?
SMB8J40CAHM3_B/I has a typical junction-to-lead thermal resistance (RθJL) of 20 °C/W and junction-to-ambient (RθJA) of 72 °C/W when mounted on 5.0 mm × 5.0 mm copper pads per JEDEC standards. This low RθJL enables efficient heat transfer to the PCB during repetitive surge events, supporting reliable operation in thermally demanding locations such as power distribution boxes or under-hood ECUs. The SMB8J40CAHM3_B/I's thermal performance is validated across its full -55 °C to +150 °C operating range.
How does the HM3 suffix differentiate SMB8J40CAHM3_B/I from other variants?
The HM3 suffix on SMB8J40CAHM3_B/I indicates halogen-free, RoHS-compliant construction with JESD201 Class 2 whisker resistance - distinguishing it from E3 (RoHS commercial), HE3 (AEC-Q101 RoHS), and M3 (halogen-free commercial) variants. Only HM3 and HE3 carry AEC-Q101 qualification, but HM3 adds halogen-free compliance required by Tier 1 automotive suppliers. The "B/I" denotes 13-inch tape-and-reel packaging (3200 units/reel), ensuring compatibility with high-speed SMT placement equipment used in automotive electronics manufacturing. SMB8J40CAHM3_B/I thus uniquely satisfies all three criteria: automotive qualification, halogen-free materials, and industrial packaging.
SMB8J40CAHM3_B/I Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-214AA, SMB
- Series:
- TransZorb®
- 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:
- 64.5V
- Current - Peak Pulse (10/1000µs):
- 12.4A
- Power - Peak Pulse:
- 800W
- Power Line Protection:
- No
- Applications:
- Telecom
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMB)
SMB8J40CAHM3_B/I FAQ
1.How can I place an order for SMB8J40CAHM3_B/I through Aetrix?
Please submit a Request for Quotation (RFQ) for SMB8J40CAHM3_B/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 SMB8J40CAHM3_B/I reliable?
The price and inventory of SMB8J40CAHM3_B/I are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMB8J40CAHM3_B/I is usually 5 days.
3.What payment methods are accepted for SMB8J40CAHM3_B/I?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMB8J40CAHM3_B/I transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMB8J40CAHM3_B/I?
SMB8J40CAHM3_B/I orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMB8J40CAHM3_B/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 SMB8J40CAHM3_B/I?
For technical support, including SMB8J40CAHM3_B/I datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMB8J40CAHM3_B/I requirements.
6.How does Aetrix verify that SMB8J40CAHM3_B/I is sourced from the original manufacturer or authorized distributors?
All SMB8J40CAHM3_B/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 SMB8J40CAHM3_B/I meets industry standards.
7.What is the process for return or replacement of SMB8J40CAHM3_B/I?
All SMB8J40CAHM3_B/I units undergo pre-shipment inspection (PSI). If there is an issue with SMB8J40CAHM3_B/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 SMB8J40CAHM3_B/I part is unused and in its original packaging.
Return procedure for SMB8J40CAHM3_B/I:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMB8J40CAHM3_B/I Tags
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