My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMAJ18A-E3/61
- Part No.:
- SMAJ18A-E3/61
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ18A-E3/61.pdf
- Description:
- TVS DIODE 18VWM 29.2VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:16,589
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ18A-E3/61 from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMA (DO-214AC) package, designed for clamping voltage transients on power and signal lines. It features a 18 V stand-off voltage (VWM), 20.0–22.1 V breakdown voltage (VBR) at 1 mA, 29.2 V maximum clamping voltage (VC) at 13.7 A peak pulse current, and 400 W peak pulse power rating with 10/1000 μs waveform - used to protect MOSFETs, ICs, and sensor interfaces in industrial and automotive electronics.
For engineers reviewing the SMAJ18A-E3/61 datasheet, SMAJ18A-E3/61 pinout, SMAJ18A-E3/61 application, or SMAJ18A-E3/61 equivalent, key selection criteria include unidirectional polarity, 1.0 μA max reverse leakage at 18 V, -55 °C to +150 °C operating junction temperature, RoHS-compliant matte tin-plated leads, and AEC-Q101 qualification eligibility via HE3 suffix variants.
Technical Context
This TVS diode operates as a fast-acting shunt protector: under normal bias it presents high impedance (<1.0 μA leakage at VWM), then avalanches within picoseconds when transient voltage exceeds VBR, clamping the line to ≤29.2 V at 13.7 A. Its glass-passivated junction ensures stable breakdown and low incremental surge resistance.
Thermally, it exhibits RθJA = 120 °C/W (on 0.2" × 0.2" copper pads) and RθJL = 30 °C/W, enabling reliable operation up to 150 °C junction temperature. The SMA package supports automated placement and meets MSL Level 1 (260 °C reflow peak).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 18 V - Maximum continuous reverse working voltage before clamping begins; defines safe operating margin for 18 V nominal rails. |
| VBR (min/max) | 20.0 V / 22.1 V at 1 mA - Confirmed breakdown threshold range; ensures predictable turn-on across process variation and temperature. |
| VC @ IPPM | 29.2 V at 13.7 A - Clamped voltage during 10/1000 μs surge; limits stress on downstream 3.3 V or 5 V logic and power stages. |
| PPPM | 400 W - Peak pulse power handling capability; sufficient for IEC 61000-4-5 Level 3 (1 kV/42 Ω) surges on 12–24 V systems. |
| IFSM | 40 A - Non-repetitive forward surge current rating (8.3 ms half-sine); supports protection against load dump events in automotive 12 V circuits. |
| TJ Range | -55 °C to +150 °C - Full automotive-grade thermal operating envelope; validated for under-hood and industrial control environments. |
| Leakage @ VWM | ≤1.0 μA - Ultra-low reverse leakage preserves battery life and signal integrity in always-on sensor and communication circuits. |
Pinout & Package
Package: SMA (DO-214AC), surface-mount, low-profile case with matte tin-plated leads solderable per J-STD-002 and JESD 22-B102. Cathode indicated by band; anode is unmarked end.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Transient current sink node | Connected to protected line; conducts avalanche current to ground during overvoltage events. |
| Anode (unbanded end) | Reference/return path | Typically tied to system ground or low-impedance return plane; completes clamping path for unidirectional operation. |
Key Features
| Feature | Design Value |
|---|---|
| 400 W peak pulse power (10/1000 μs) | Enables robust protection against IEC 61000-4-5 surges without derating below 78 V - critical for 12–48 V industrial power rails. |
| Glass passivated junction | Ensures stable VBR tolerance (±5 %), low leakage drift over temperature, and long-term reliability in humid or thermally cycling environments. |
| MSL Level 1 compliance | Supports single-reflow assembly at 260 °C peak without moisture-induced popcorning - eliminates pre-bake requirements in high-volume SMT lines. |
| AEC-Q101 qualification option | HE3/HM3 variants are automotive-qualified; enables drop-in use in ADAS camera modules, body control units, and infotainment power supplies. |
| Low profile SMA package | 0.208" × 0.157" footprint with 0.090" height fits dense PCB layouts; compatible with standard 7" tape-and-reel (E3/61) feeding equipment. |
Applications
| Automotive Power Line Protection | Industrial Sensor Interface Protection |
|---|---|
Use Scenario: Protecting 12 V supply inputs of ECUs and lighting controllers from load dump and ISO 7637-2 pulses. IC Role / Device Role / Timing Role: Unidirectional shunt TVS placed between power rail and chassis ground to clamp transients <100 ns after onset. Use Value: Limits clamped voltage to 29.2 V, preventing damage to 36 V-rated DC-DC converters and microcontrollers with 40 V absolute max ratings. |
Use Scenario: Safeguarding analog outputs (e.g., 4–20 mA loops) and digital I/O (CAN, LIN) of pressure/temperature sensors in factory automation. IC Role / Device Role / Timing Role: Fast-response voltage clamp on signal lines, positioned adjacent to connector entry points to intercept ESD and inductive kickback. Use Value: Sub-μA leakage preserves loop accuracy; 29.2 V clamping prevents latch-up in op-amps and transceivers rated for ≤36 V supply. |
| Consumer Power Adapter Input Protection | Telecom DC Power Feeding Protection |
Use Scenario: Secondary-side overvoltage suppression in AC/DC adapters for USB-C PD and laptop chargers. IC Role / Device Role / Timing Role: Standoff-rated TVS on +VOUT rail to absorb flyback spikes from transformer leakage inductance during regulation faults. Use Value: 18 V VWM aligns with 19 V nominal adapter outputs; 400 W rating handles repetitive switching surges without thermal runaway. |
Use Scenario: DC feed protection in PoE-powered access points and remote radio units where 48 V phantom power is delivered over Ethernet pairs. IC Role / Device Role / Timing Role: Unidirectional TVS on PSE side to suppress induced surges from lightning coupling or cable discharge events. Use Value: 29.2 V clamping ensures compatibility with IEEE 802.3bt Class 5/6 PSE controllers; RoHS/E3 compliance meets telecom environmental mandates. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A-M3/61 | Halogen-free, RoHS-compliant variant; identical electrical specs and package; same 18 V VWM, 29.2 V VC, and 400 W PPPM. | Required where halogen-free material compliance is mandated (e.g., EU public infrastructure, medical devices). | Select SMAJ18A-M3/61 when halogen-free composition is contractually required; no layout or performance trade-offs. |
| SMAJ18CA-E3/61 | Bidirectional version; symmetric VBR (20.0–22.1 V) in both directions; same VC (29.2 V), PPPM (400 W), and package. | Suitable for AC-coupled or floating signal lines (e.g., RS-485, audio, differential sensors) where polarity reversal may occur. | Choose SMAJ18CA-E3/61 only for bidirectional threat models; unidirectional SMAJ18A-E3/61 offers lower leakage and simpler grounding in DC power applications. |
Compared with SMAJ18A-M3/61, the E3/61 variant uses standard RoHS-compliant materials without halogen restriction; compared with SMAJ18CA-E3/61, the unidirectional configuration provides tighter leakage control and avoids unnecessary bidirectional conduction in grounded DC systems.
Availability
SMAJ18A-E3/61 is available at Aetrix Electronics and suitable for automotive ECU protection, industrial sensor interface hardening, and consumer power adapter surge suppression requiring stable component supply and full traceability.
Supply support for SMAJ18A-E3/61 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, TVS devices, and optoelectronics with emphasis on reliability, precision, and application-specific optimization.
The SMAJ series was engineered for high-energy transient suppression in space-constrained, high-reliability applications - particularly targeting automotive, industrial, and telecom power and signal line protection where fast response and repeatable clamping are mandatory.
FAQ
What is the clamping voltage of SMAJ18A-E3/61 at its rated peak pulse current?
The SMAJ18A-E3/61 has a maximum clamping voltage (VC) of 29.2 V at its specified peak pulse current (IPPM) of 13.7 A, measured using the standardized 10/1000 μs double-exponential waveform. This value ensures downstream components with 30–36 V absolute maximum ratings remain within safe operating limits during surge events. The clamping performance is guaranteed across the full -55 °C to +150 °C junction temperature range.
Is SMAJ18A-E3/61 suitable for automotive applications?
SMAJ18A-E3/61 itself is commercial-grade, but Vishay offers the functionally identical SMAJ18AHE3_A variant (AEC-Q101 qualified) in the same SMA package. For automotive use, engineers should specify the HE3 suffix; the E3/61 version is appropriate for industrial and consumer designs where AEC-Q101 is not mandated. Both share identical electrical parameters including 18 V VWM, 20.0–22.1 V VBR, and 29.2 V VC.
What does the "/61" suffix indicate in SMAJ18A-E3/61?
The "/61" suffix in SMAJ18A-E3/61 denotes the preferred packaging format: 7-inch diameter plastic tape and reel containing 1800 units. This is the standard shipping configuration for high-volume SMT assembly. The "E3" indicates RoHS-compliant, commercial-grade construction with matte tin-plated leads. No electrical or thermal differences exist between /61 and other packaging codes like /5A (13" reel, 7500 units).
How does SMAJ18A-E3/61 compare to SMAJ15A-E3/61 in terms of voltage ratings?
SMAJ18A-E3/61 has a higher stand-off voltage (VWM = 18 V) and breakdown range (20.0–22.1 V) than SMAJ15A-E3/61 (VWM = 15 V, VBR = 16.7–18.5 V), making it suitable for 18 V nominal systems. Its clamping voltage is also higher (29.2 V vs. 24.4 V), allowing protection of components with wider voltage tolerances. Both share identical 400 W PPPM, 120 °C/W RθJA, and SMA package dimensions.
Can SMAJ18A-E3/61 be used in bidirectional signal protection?
No - SMAJ18A-E3/61 is unidirectional and must be oriented with cathode toward the protected line and anode to ground. For bidirectional signal lines (e.g., RS-485, USB D+/D−), the SMAJ18CA-E3/61 variant is required. Using SMAJ18A-E3/61 on AC or floating signals risks forward conduction during negative transients, leading to failure or incorrect clamping behavior.
SMAJ18A-E3/61 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):
- 18V
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 29.2V
- Current - Peak Pulse (10/1000µs):
- 13.7A
- Power - Peak Pulse:
- 400W
- 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-214AC (SMA)
SMAJ18A-E3/61 FAQ
1.How can I place an order for SMAJ18A-E3/61 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ18A-E3/61 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 SMAJ18A-E3/61 reliable?
The price and inventory of SMAJ18A-E3/61 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ18A-E3/61 is usually 5 days.
3.What payment methods are accepted for SMAJ18A-E3/61?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ18A-E3/61 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ18A-E3/61?
SMAJ18A-E3/61 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ18A-E3/61 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 SMAJ18A-E3/61?
For technical support, including SMAJ18A-E3/61 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ18A-E3/61 requirements.
6.How does Aetrix verify that SMAJ18A-E3/61 is sourced from the original manufacturer or authorized distributors?
All SMAJ18A-E3/61 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 SMAJ18A-E3/61 meets industry standards.
7.What is the process for return or replacement of SMAJ18A-E3/61?
All SMAJ18A-E3/61 units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ18A-E3/61, 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 SMAJ18A-E3/61 part is unused and in its original packaging.
Return procedure for SMAJ18A-E3/61:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ18A-E3/61 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 …
