My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMB8J18CA-M3/5B
;;2.jpg)
- Part No.:
- SMB8J18CA-M3/5B
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMB8J18CA-M3/5B.pdf
- Description:
- TVS DIODE 18VWM 29.2VC DO214AA
- Quantity:
- Payment:
- Shipping:
Inventory:3,550
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMB8J18CA-M3/5B from Vishay General Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in SMB (DO-214AA) package, designed for high-energy surge protection on signal and power lines. It features a 18 V stand-off voltage (VWM), 29.2 V clamping voltage (VC) at 27.4 A peak pulse current (IPPM), and 800 W peak pulse power (PPPM) with 10/1000 μs waveform - used to safeguard automotive sensor interfaces, industrial I/O ports, and telecom line drivers against ESD and load-switching transients.
For engineers reviewing the SMB8J18CA-M3/5B datasheet, SMB8J18CA-M3/5B pinout, SMB8J18CA-M3/5B application, or SMB8J18CA-M3/5B equivalent, key selection criteria include bidirectional clamping capability, AEC-Q101 qualification, halogen-free RoHS compliance (M3 suffix), and compatibility with automated SMT placement on 5.0 mm × 5.0 mm copper pads.
Technical Context
This TVS diode operates as a voltage-clamped shunt protector: under normal conditions it presents high impedance (>1 μA leakage at 18 V), but triggers into low-impedance conduction when reverse voltage exceeds its 20.0–22.1 V breakdown range (VBR at 1 mA). Its glass-passivated junction ensures stable avalanche behavior and fast response (<1 ns), while the SMB package provides 72 °C/W junction-to-ambient thermal resistance for reliable power dissipation during transient events.
The device is rated for -55 °C to +150 °C operating junction temperature and meets MSL Level 1 per J-STD-020 (peak reflow 260 °C). Its bidirectional symmetry enables protection of AC-coupled or differential lines without polarity concerns, and AEC-Q101 qualification confirms suitability for automotive under-hood and body-control module applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 18 V - maximum continuous reverse working voltage before clamping begins |
| VBR (min/max) | 20.0 V / 22.1 V - breakdown voltage range at 1 mA test current; defines turn-on threshold tolerance |
| VC @ IPPM | 29.2 V at 27.4 A - clamping voltage during 10/1000 μs surge; limits protected circuit stress |
| PPPM | 800 W - peak pulse power handling with 10/1000 μs waveform; determines surge energy capacity |
| ID @ VWM | 1.0 μA - reverse leakage at stand-off voltage; ensures minimal standby power loss |
| TJ max. | +150 °C - maximum junction temperature; supports operation in hot automotive environments |
| Package | SMB (DO-214AA) - surface-mount outline with 5.59 mm × 4.06 mm footprint and 2.20 mm height |
Pinout & Package
SMB8J18CA-M3/5B uses the standard SMB (DO-214AA) package: two-terminal, non-polarized bidirectional device with no cathode marking. The case is molded compound meeting UL 94 V-0; terminals are matte tin-plated for solderability per J-STD-002.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Transient current path | Both terminals function identically; bidirectional clamping allows connection across any two points needing overvoltage protection |
| Case (body) | Thermal and mechanical interface | Non-conductive plastic body; heat transfer occurs via leads to PCB copper pads (recommended 5.0 mm × 5.0 mm per terminal) |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive-grade reliability including temperature cycling, humidity bias, and mechanical shock testing |
| Halogen-free & RoHS-compliant (M3) | Meets environmental regulations without compromising surge performance or thermal stability |
| Low incremental surge resistance | Enables tight clamping (29.2 V at 27.4 A) and minimizes let-through voltage during fast transients |
| MSL Level 1 rating | Supports lead-free reflow up to 260 °C peak without moisture-induced damage |
| Glass-passivated junction | Ensures consistent avalanche characteristics, low leakage, and long-term parameter stability under repeated surges |
Applications
| Automotive Sensor Protection | Industrial PLC I/O Protection |
|---|---|
Use Scenario: Protecting CAN bus transceivers and analog sensor inputs (e.g., pressure, temperature) in engine control units from load-dump and ISO 7637-2 pulses. IC Role / Device Role / Timing Role: Shunt-type transient suppressor placed directly at connector or IC input pins to clamp voltage spikes before they reach sensitive circuitry. Use Value: Maintains signal integrity by limiting transient overvoltage to ≤29.2 V while surviving 800 W surges - critical for AEC-Q100-compliant microcontrollers and analog front-ends. | Use Scenario: Safeguarding digital input/output channels on programmable logic controller (PLC) modules exposed to relay coil flyback and field wiring surges. IC Role / Device Role / Timing Role: Bidirectional voltage clamp on 24 V DC I/O lines, absorbing both positive and negative polarity transients induced by inductive switching. Use Value: Eliminates need for separate unidirectional devices per line; 27.4 A peak surge current rating handles typical 24 V industrial transients without degradation. |
| Telecom Line Driver Protection | Consumer USB/Display Interface Protection |
Use Scenario: Shielding RS-485 transceivers and Ethernet PHYs in base station equipment from lightning-induced surges on long cable runs. IC Role / Device Role / Timing Role: Primary-level TVS placed at board edge connectors to divert surge energy away from data-line ESD protection arrays and signal conditioning ICs. Use Value: 800 W PPPM and 29.2 V VC ensure robust first-stage clamping that reduces stress on downstream TVS diodes or integrated protection in PHY ICs. | Use Scenario: Adding secondary surge protection to USB 2.0 data lines and LVDS display interfaces in laptops and monitors where internal ESD protection is insufficient for system-level IEC 61000-4-5 testing. IC Role / Device Role / Timing Role: Low-capacitance (typ. <100 pF) bidirectional clamp placed between connector and controller IC to suppress 1 kV/42 Ω combination wave surges. Use Value: Prevents latch-up and permanent damage in high-speed interfaces while maintaining signal integrity due to fast <1 ns response and symmetric clamping behavior. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ18CA-M3/5B | 1000 W PPPM (unidirectional variant); same VWM/VBR/VC but higher power rating and unidirectional polarity | Requires polarity-aware layout; not suitable for AC or differential lines without external biasing | Select when higher single-polarity surge margin is needed and circuit topology permits directional placement |
| SMAJ18CA-M3/5B | Lower 400 W PPPM; SMA package (smaller footprint, higher RθJA = 110 °C/W) | Limited to lower-energy transients; less thermal margin in high-ambient or high-duty-cycle environments | Choose for space-constrained designs where 400 W surge capability suffices and thermal derating is acceptable |
Compared with SMBJ18CA-M3/5B and SMAJ18CA-M3/5B, SMB8J18CA-M3/5B delivers balanced bidirectional 800 W protection in an industry-standard SMB footprint - offering optimal trade-off between surge robustness, layout flexibility, and thermal performance for automotive and industrial applications requiring polarity-agnostic clamping.
Availability
SMB8J18CA-M3/5B is available at Aetrix Electronics and suitable for automotive electronics, industrial control systems, and telecommunications infrastructure requiring stable component supply with full traceability and lifecycle management.
Supply support for SMB8J18CA-M3/5B 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 application-specific optimization.
The SMB8JxxCA series belongs to Vishay's TRANSZORB® family of high-power-density TVS diodes, engineered specifically for AEC-Q101-compliant automotive and harsh-environment industrial surge protection where bidirectional clamping and halogen-free compliance are mandatory.
FAQ
What is the clamping voltage of SMB8J18CA-M3/5B at its rated peak pulse current?
The SMB8J18CA-M3/5B has a maximum clamping voltage (VC) of 29.2 V when subjected to its specified peak pulse current (IPPM) of 27.4 A under a 10/1000 μs waveform. This value is measured per ANSI/IEEE C62.35 standards and ensures protected circuits experience limited overvoltage stress during surge events. The SMB8J18CA-M3/5B maintains this clamping performance across its qualified operating temperature range.
Is SMB8J18CA-M3/5B suitable for automotive applications?
Yes, SMB8J18CA-M3/5B is AEC-Q101 qualified and explicitly designed for automotive use, including engine control units, body electronics, and ADAS sensor interfaces. Its halogen-free (M3) construction, MSL Level 1 reflow rating, and -55 °C to +150 °C operating range meet stringent automotive reliability requirements. The SMB8J18CA-M3/5B is listed in Vishay's automotive-grade product portfolio with full qualification test reports available upon request.
How does the bidirectional configuration of SMB8J18CA-M3/5B affect its circuit implementation?
The bidirectional nature of SMB8J18CA-M3/5B means it functions identically in either orientation - no cathode marking is present, and it clamps both positive and negative transients equally. This simplifies PCB layout for AC-coupled signals, differential buses (e.g., RS-485), or any line where voltage polarity reversal is possible. Unlike unidirectional TVS diodes, the SMB8J18CA-M3/5B eliminates polarity verification during assembly and avoids misplacement risk in automated SMT processes.
What is the thermal resistance of SMB8J18CA-M3/5B, and how does it impact layout design?
SMB8J18CA-M3/5B has a typical junction-to-ambient thermal resistance (RθJA) of 72 °C/W when mounted on 5.0 mm × 5.0 mm copper pads per terminal. This value assumes minimum recommended pad layout per Vishay's datasheet; reducing pad area increases thermal resistance and requires derating of surge capability at elevated ambient temperatures. For sustained or repetitive surge conditions, designers must consult Figure 2 in the SMB8J18CA-M3/5B datasheet to apply appropriate thermal derating curves.
Does SMB8J18CA-M3/5B meet RoHS and halogen-free requirements?
Yes, the "M3" suffix in SMB8J18CA-M3/5B indicates halogen-free, RoHS-compliant construction per JEDEC JS-001 and Vishay specification 99912. The molding compound contains no brominated flame retardants or chlorine-based additives, and all terminations use matte tin plating compliant with JESD 22-B102. This makes SMB8J18CA-M3/5B suitable for environmentally regulated markets including EU automotive and industrial equipment.
SMB8J18CA-M3/5B 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):
- 18V
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 29.2V
- Current - Peak Pulse (10/1000µs):
- 27.4A
- Power - Peak Pulse:
- 800W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AA (SMBJ)
SMB8J18CA-M3/5B FAQ
1.How can I place an order for SMB8J18CA-M3/5B through Aetrix?
Please submit a Request for Quotation (RFQ) for SMB8J18CA-M3/5B 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 SMB8J18CA-M3/5B reliable?
The price and inventory of SMB8J18CA-M3/5B are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMB8J18CA-M3/5B is usually 5 days.
3.What payment methods are accepted for SMB8J18CA-M3/5B?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMB8J18CA-M3/5B transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMB8J18CA-M3/5B?
SMB8J18CA-M3/5B orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMB8J18CA-M3/5B 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 SMB8J18CA-M3/5B?
For technical support, including SMB8J18CA-M3/5B datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMB8J18CA-M3/5B requirements.
6.How does Aetrix verify that SMB8J18CA-M3/5B is sourced from the original manufacturer or authorized distributors?
All SMB8J18CA-M3/5B 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 SMB8J18CA-M3/5B meets industry standards.
7.What is the process for return or replacement of SMB8J18CA-M3/5B?
All SMB8J18CA-M3/5B units undergo pre-shipment inspection (PSI). If there is an issue with SMB8J18CA-M3/5B, 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 SMB8J18CA-M3/5B part is unused and in its original packaging.
Return procedure for SMB8J18CA-M3/5B:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMB8J18CA-M3/5B 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 …
