My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMB8J40CAHM3/I
- Part No.:
- SMB8J40CAHM3/I
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMB8J40CAHM3/I.pdf
- Description:
- TVS DIODE 40VWM 64.5VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:4,704
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMB8J40CAHM3/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), 64.5 V maximum 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 sensor interface and industrial I/O line protection.
For engineers reviewing the SMB8J40CAHM3/I datasheet, SMB8J40CAHM3/I pinout, SMB8J40CAHM3/I application, or SMB8J40CAHM3/I equivalent, this device is evaluated for AEC-Q101-compliant transient suppression in 12 V/24 V automotive systems, DC power rail hardening, and bidirectional data line surge immunity where low-leakage (<1.0 µA at VWM) and fast response (<1 ns) are critical.
Technical Context
This bidirectional TVS operates symmetrically across both polarities, enabling robust protection against ESD, lightning-induced surges, and inductive switching transients without polarity sensitivity. Its glass-passivated junction ensures stable breakdown behavior and low incremental surge resistance under repetitive stress.
Rated for -55 °C to +150 °C operation and qualified to AEC-Q101, SMB8J40CAHM3/I supports automotive-grade reliability with MSL Level 1 moisture sensitivity and halogen-free, RoHS-compliant construction (HM3 suffix). Thermal resistance is 72 °C/W (junction-to-ambient) on standard 5.0 mm × 5.0 mm copper pads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 40 V - Maximum continuous reverse operating voltage before clamping begins; defines safe DC bias margin for 24 V nominal systems. |
| VBR min/max | 44.4 V / 49.1 V at 1.0 mA - Verified breakdown threshold range ensures consistent turn-on across production lots and temperature. |
| VC @ IPPM | 64.5 V at 12.4 A - Clamping voltage during 10/1000 µs surge; limits downstream IC stress to safe levels in 48 V automotive subsystems. |
| PPPM | 800 W - Peak pulse power handling capacity; enables protection against ISO 7637-2 Pulse 1/2a/5a and IEC 61000-4-5 Level 3 surges. |
| ID @ VWM | ≤1.0 µA - Ultra-low reverse leakage preserves battery life and signal integrity in always-on automotive modules. |
| TJ max | +150 °C - Junction temperature rating supports under-hood deployment and sustained operation in thermally constrained enclosures. |
Pinout & Package
Package: SMB (DO-214AA), surface-mount, halogen-free, matte tin-plated leads. Dimensions: 4.57 mm × 3.94 mm × 2.20 mm (L × W × H); cathode band absent (bidirectional symmetry).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Bidirectional surge conduction path | No polarity marking; terminals interchangeable - simplifies PCB layout and eliminates orientation errors during automated placement. |
| Case (body) | Thermal and mechanical interface | Plastic molding meets UL 94 V-0; thermal path optimized via 5.0 mm × 5.0 mm copper pad per terminal per datasheet fig. 2. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive electronics - includes HTOL, TC, UHAST, and ESD testing per stress test plan. |
| Low-profile SMB package | 2.20 mm height enables use in space-constrained modules such as ADAS camera ECUs and body control units. |
| Glass-passivated junction | Ensures stable VBR over lifetime and immunity to humidity-induced parameter drift in harsh environments. |
| MSL Level 1 rating | Allows unlimited floor life and reflow up to 260 °C peak - compatible with standard lead-free SMT assembly processes. |
Applications
| Automotive Sensor Interface | Industrial CAN Bus Protection |
|---|---|
Use Scenario: Protecting analog outputs of pressure/temperature sensors connected to 12 V vehicle battery rails. IC Role / Device Role / Timing Role: Bidirectional clamping element placed between sensor output and microcontroller ADC input. Use Value: Limits transients from load dump or alternator ripple to ≤64.5 V, preserving 12-bit ADC accuracy and preventing latch-up in downstream MCU. |
Use Scenario: Surge suppression on CAN_H/CAN_L lines in factory automation gateways exposed to motor drive noise. IC Role / Device Role / Timing Role: Low-capacitance TVS pair (one per line) placed adjacent to CAN transceiver I/O pins. Use Value: Maintains <1.0 µA leakage at 12 V bias while clamping 1 kV/500 A IEC 61000-4-5 surges to safe levels without distorting 1 Mbps CAN signaling. |
| DC Power Rail Hardening | Telecom Line Interface |
Use Scenario: Input-stage protection for 24 V DC-DC converters powering infotainment head units. IC Role / Device Role / Timing Role: Primary surge limiter upstream of input filter capacitor and controller IC. Use Value: Absorbs 800 W pulses without degradation, enabling compliance with ISO 16750-2 Load Dump Test (Pulse 5a) without derating. |
Use Scenario: Overvoltage protection on RS-485/RS-422 differential pairs in outdoor telecom base station controllers. IC Role / Device Role / Timing Role: Symmetric TVS pair bridging differential lines to ground, referenced to local chassis potential. Use Value: Withstands repeated 10/1000 µs surges up to 800 W while maintaining <0.5 pF junction capacitance per line - no signal integrity impact at 10 Mbps. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMB8J40CAHE3/I | RoHS-compliant but not halogen-free; lacks HM3 material certification. | Approved for commercial/industrial use only - not AEC-Q101 qualified. | Select when automotive qualification is unnecessary and cost optimization is prioritized. |
| SMAJ40CA | Lower PPPM (400 W), larger SMA package (DO-214AC), higher RθJA (90 °C/W). | Requires larger PCB area and delivers lower surge energy handling; unsuitable for ISO 7637-2 Pulse 5a. | Choose only for legacy designs with existing SMA footprints and reduced surge requirements. |
Compared with SMB8J40CAHM3/I, SMB8J40CAHE3/I omits halogen-free compliance and automotive qualification, while SMAJ40CA sacrifices 50 % peak power rating and thermal performance due to smaller junction area and less efficient thermal pad layout.
Availability
SMB8J40CAHM3/I is available at Aetrix Electronics and suitable for automotive sensor interfaces, industrial CAN bus nodes, and DC power rail hardening requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for SMB8J40CAHM3/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, MOSFETs, optoelectronics, and passive components with emphasis on reliability and automotive-grade validation.
The SMB8JxxCA series belongs to Vishay's TRANSZORB® TVS platform, engineered specifically for high-power-density, AEC-Q101-compliant transient suppression in automotive and industrial power/signal lines.
FAQ
What is the clamping voltage of SMB8J40CAHM3/I at its rated peak pulse current?
The SMB8J40CAHM3/I has a maximum clamping voltage (VC) of 64.5 V at 12.4 A peak pulse current (IPPM) under 10/1000 µs waveform conditions. This value is measured per ANSI/IEEE C62.35 and guarantees predictable voltage limiting during surge events, directly protecting downstream 65 V-rated ICs in 24 V automotive systems.
Is SMB8J40CAHM3/I suitable for automotive applications?
Yes, SMB8J40CAHM3/I is AEC-Q101 qualified and carries the HM3 suffix indicating halogen-free, RoHS-compliant construction. It is explicitly rated for automotive use per Vishay's ordering nomenclature and meets MSL Level 1, making it appropriate for engine control units, ADAS sensors, and body electronics deployed in vehicles.
What does the "HM3" suffix mean in SMB8J40CAHM3/I?
The "HM3" suffix in SMB8J40CAHM3/I denotes halogen-free, RoHS-compliant, and AEC-Q101-qualified construction. It distinguishes this variant from commercial-grade versions (e.g., E3/M3) and confirms compliance with automotive material standards and reliability testing protocols defined in the Vishay datasheet 88422.
How does SMB8J40CAHM3/I differ from unidirectional variants like SMB10J40A?
SMB8J40CAHM3/I is bidirectional with symmetrical clamping in both polarities and 800 W PPPM, whereas SMB10J40A is unidirectional with 1000 W PPPM and a cathode band marking. The SMB8J40CAHM3/I supports AC-coupled or polarity-agnostic protection, while SMB10J40A requires correct orientation and handles higher single-polarity surge energy.
What is the thermal resistance of SMB8J40CAHM3/I under standard mounting conditions?
SMB8J40CAHM3/I has a typical junction-to-ambient thermal resistance (RθJA) of 72 °C/W when mounted on 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal, as specified in Vishay document 88422. This value assumes JEDEC-standard board layout and is critical for calculating steady-state temperature rise during repetitive surge events.
SMB8J40CAHM3/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:
- Discontinued at Digi-Key
- 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/I FAQ
1.How can I place an order for SMB8J40CAHM3/I through Aetrix?
Please submit a Request for Quotation (RFQ) for SMB8J40CAHM3/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/I reliable?
The price and inventory of SMB8J40CAHM3/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/I is usually 5 days.
3.What payment methods are accepted for SMB8J40CAHM3/I?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMB8J40CAHM3/I transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMB8J40CAHM3/I?
SMB8J40CAHM3/I orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMB8J40CAHM3/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/I?
For technical support, including SMB8J40CAHM3/I datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMB8J40CAHM3/I requirements.
6.How does Aetrix verify that SMB8J40CAHM3/I is sourced from the original manufacturer or authorized distributors?
All SMB8J40CAHM3/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/I meets industry standards.
7.What is the process for return or replacement of SMB8J40CAHM3/I?
All SMB8J40CAHM3/I units undergo pre-shipment inspection (PSI). If there is an issue with SMB8J40CAHM3/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/I part is unused and in its original packaging.
Return procedure for SMB8J40CAHM3/I:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMB8J40CAHM3/I Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
