My Inquiry
My Account
Taiwan Semiconductor Corporation SMA6J18A
- Part No.:
- SMA6J18A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMA6J18A.pdf
- Description:
- TVS DIODE 18VWM 28.3VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:7,869
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMA6J18A from Taiwan Semiconductor is a 600W surface-mount transient voltage suppressor (TVS) diode with a working standoff voltage of 18 V, breakdown voltage range 20–22.1 V, and clamping voltage of 28.3 V at 21.2 A peak pulse current; used for surge protection in DC/DC converters and power adapters.
For engineers reviewing the SMA6J18A datasheet, SMA6J18A pinout, SMA6J18A application, or SMA6J18A equivalent, key selection criteria include clamping performance under 10/1000 µs transients, ISO 7637-2 compliance for automotive load-dump immunity, DO-214AC package thermal and mechanical suitability, and junction temperature rating up to +175°C.
Technical Context
The SMA6J18A operates as a unidirectional avalanche diode configured in a single-die DO-214AC package, designed to clamp transient overvoltages by entering avalanche breakdown when reverse voltage exceeds VBR (20–22.1 V). Its glass-passivated junction ensures stable leakage (<1 µA at 18 V) and fast response (<1.0 ps).
It delivers 600 W peak pulse power per 10/1000 µs waveform with a maximum clamping voltage of 28.3 V at 21.2 A, meeting ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b test requirements for automotive electronics and industrial power systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 18 V - Maximum continuous reverse operating voltage before conduction begins |
| VBR @ IT=1 mA | 20–22.1 V - Breakdown voltage range defining reliable avalanche initiation threshold |
| VC @ IPPM=21.2 A | 28.3 V - Clamped voltage during 10/1000 µs surge, limiting downstream circuit stress |
| PPPM | 600 W - Peak pulse power handling capability under standardized surge waveform |
| IPPM | 21.2 A - Maximum non-repetitive peak current the device safely clamps without failure |
| TJ max | +175 °C - Maximum junction temperature enabling operation in high-ambient environments |
| Package | DO-214AC (SMA) - Standardized surface-mount outline with cathode band polarity marking |
Pinout & Package
DO-214AC (SMA) package: molded plastic case with matte tin-plated leads, cathode indicated by band, weight ≈ 0.060 g, UL 94V-0 rated compound, JESD201 Class 2 whisker resistant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward current entry / low-side reference | Connected to system ground or lower-potential rail in unidirectional TVS configuration |
| Cathode | Reverse-biased surge input / clamping node | Connected to protected line (e.g., 18 V rail); conducts during overvoltage to shunt energy to ground |
Key Features
| Feature | Design Value |
|---|---|
| Clamping voltage at rated IPPM | 28.3 V ensures downstream ICs rated for 30 V logic or power rails remain within safe operating limits |
| Response time | <1.0 ps enables suppression before transient energy couples into sensitive analog or digital circuitry |
| ISO 7637-2 compliance | Validated for Pulse 1 (inductive load dump), 2a/2b (battery disconnect/connect), and 3a/3b (capacitive coupling) ensures robustness in automotive ECUs |
| Moisture sensitivity level | Level 1 per J-STD-020 eliminates bake requirements prior to reflow, simplifying SMT assembly |
| RoHS & halogen-free | Complies with IEC 61249-2-21 and EU RoHS directives for environmentally constrained applications |
Applications
| Switching Mode Power Supply (SMPS) | Automotive On-Board DC/DC Converter |
|---|---|
Use Scenario: Protection of primary-side MOSFET gate drivers and secondary-side rectifiers against switching-induced voltage spikes and ESD events. IC Role / Device Role: Unidirectional TVS placed across input/output rails to clamp transients before they reach controller ICs or power stages. Use Value: 28.3 V clamping at 21.2 A prevents latch-up or oxide rupture in 24 V-rated controllers while maintaining 600 W surge margin. | Use Scenario: Load-dump and jump-start surge suppression on 12 V/24 V battery-fed DC/DC modules powering infotainment or ADAS sensors. IC Role / Device Role: Primary-line TVS connected between battery rail and ground, activated during ISO 7637-2 Pulse 2b (load dump) events. Use Value: Meets Pulse 2b peak clamping requirement with <28.3 V clamping at 21.2 A, preserving 30 V-rated buck converter ICs. |
| LED Lighting Driver | Industrial AC/DC Adapter |
Use Scenario: Input-stage protection for constant-current LED drivers subjected to lightning-induced surges on long cable runs. IC Role / Device Role: Front-end TVS on bulk capacitor input, absorbing 10/1000 µs line transients before they stress bridge rectifiers or PWM controllers. Use Value: 600 W peak power rating sustains multiple surge events without degradation; 18 V VWM avoids leakage issues in 24 V nominal systems. | Use Scenario: Secondary-side output rail protection in universal-input AC/DC adapters supplying 18–24 V to IoT gateways or PLC I/O modules. IC Role / Device Role: Output-rail TVS preventing overvoltage damage to connected microcontrollers or communication interfaces during output short-circuit recovery. Use Value: 28.3 V clamping aligns with 3.3 V/5 V LDO input tolerances when used with post-regulation filtering, ensuring clean reset 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 |
|---|---|---|---|
| Littelfuse SMAJ18A | VBR = 20–22.2 V, VC = 29.2 V @ 20.5 A, same DO-214AC package | Marginally higher clamping voltage (+0.9 V) and lower IPPM (20.5 A vs. 21.2 A) | Acceptable where 0.9 V clamping margin is available; verify layout thermal relief matches TSC's 4 W steady-state rating |
| ON Semiconductor SMA6J18A | Identical electrical specs and DO-214AC footprint; differs only in branding and traceability documentation | No functional difference; qualified for same automotive and industrial use cases | Drop-in replacement if dual-sourcing required; confirm MSL level and reflow profile alignment with Taiwan Semiconductor's Level 1 rating |
Compared with SMA6J18A, SMAJ18A offers slightly reduced surge current capacity and higher clamping, while ON Semiconductor's SMA6J18A provides identical performance with alternate supply-chain traceability-both require no PCB redesign but differ in thermal derating validation and qualification reports.
Availability
SMA6J18A is available at Aetrix Electronics and suitable for switching mode power supplies, automotive DC/DC converters, and industrial LED lighting systems requiring stable component supply and ISO 7637-2-compliant surge immunity.
Supply support for SMA6J18A 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 semiconductor manufacturer specializing in discrete power devices, TVS diodes, rectifiers, and MOSFETs for industrial and automotive markets.
The SMA6JxxA series was developed specifically for high-reliability, surface-mount transient suppression in space-constrained 12 V/24 V systems where fast response, low clamping, and AEC-Q101 readiness are critical.
FAQ
What is the maximum clamping voltage of the SMA6J18A under standard surge conditions?
The SMA6J18A has a maximum clamping voltage (VC) of 28.3 V when subjected to a 10/1000 µs waveform at its rated peak pulse current of 21.2 A. This value is measured per JEDEC standards and ensures predictable overvoltage limiting for downstream 30 V-rated components. The SMA6J18A maintains this clamping performance across its full operating temperature range of –55 °C to +175 °C.
Does the SMA6J18A meet automotive surge immunity standards?
Yes, the SMA6J18A meets ISO 7637-2 requirements for Pulse 1 (inductive switch-off), Pulse 2a/2b (battery disconnection/reconnection), and Pulse 3a/3b (capacitive coupling), making it suitable for automotive body control modules and DC/DC converters. The SMA6J18A achieves this through controlled avalanche characteristics and low dynamic impedance, validated in Taiwan Semiconductor's certified test lab per ISO 7637-2 Annex A.
What is the moisture sensitivity level (MSL) rating for the SMA6J18A?
The SMA6J18A is rated MSL Level 1 per J-STD-020, meaning it may be stored indefinitely at ambient conditions and requires no baking prior to surface-mount reflow. This simplifies manufacturing flow for high-volume SMT lines. The SMA6J18A's DO-214AC package uses moisture-resistant molding compound, and its matte tin-plated leads comply with J-STD-002 solderability requirements.
Can the SMA6J18A be used in bidirectional configurations?
No, the SMA6J18A is a unidirectional TVS diode intended for DC applications with defined polarity; its cathode band must be oriented toward the protected line. For bidirectional protection, two SMA6J18A devices in series opposition or a dedicated bidirectional part like SMA6J18CA is required. Using SMA6J18A in reverse bias beyond VWM will not provide symmetrical clamping.
What is the steady-state power dissipation rating for the SMA6J18A?
The SMA6J18A has a steady-state power dissipation (PD) rating of 4 W at 25 °C ambient, derating linearly above 25 °C per the published pulse derating curve. This rating supports continuous leakage current management and thermal stability during prolonged exposure to voltages near VWM. The SMA6J18A's 175 °C maximum junction temperature allows sustained operation in enclosed industrial enclosures without forced airflow.
SMA6J18A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AC, SMA
- Series:
- SMA6J
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 18V
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 28.3V
- Current - Peak Pulse (10/1000µs):
- 21.2A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
SMA6J18A FAQ
1.How can I place an order for SMA6J18A through Aetrix?
Please submit a Request for Quotation (RFQ) for SMA6J18A 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 SMA6J18A reliable?
The price and inventory of SMA6J18A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMA6J18A is usually 5 days.
3.What payment methods are accepted for SMA6J18A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMA6J18A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMA6J18A?
SMA6J18A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMA6J18A 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 SMA6J18A?
For technical support, including SMA6J18A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMA6J18A requirements.
6.How does Aetrix verify that SMA6J18A is sourced from the original manufacturer or authorized distributors?
All SMA6J18A 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 SMA6J18A meets industry standards.
7.What is the process for return or replacement of SMA6J18A?
All SMA6J18A units undergo pre-shipment inspection (PSI). If there is an issue with SMA6J18A, 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 SMA6J18A part is unused and in its original packaging.
Return procedure for SMA6J18A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMA6J18A 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
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 …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
