My Inquiry
My Account
Diodes Incorporated SMAJ18CA-13-F
- Part No.:
- SMAJ18CA-13-F
- Manufacturer:
- Diodes Incorporated
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ18CA-13-F.pdf
- Description:
- TVS DIODE 18VWM 29.2VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:105,450
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ18CA-13-F from Diodes Incorporated is a bidirectional 400W surface-mount transient voltage suppressor (TVS) diode designed for overvoltage protection in DC power lines and signal interfaces. It features a 18V reverse standoff voltage (VRWM), 29.2V max clamping voltage at 13.7A peak pulse current, and SMA package with glass-passivated die construction. Used in automotive infotainment power rails to suppress ESD and load-dump transients.
For engineers reviewing the SMAJ18CA-13-F datasheet, SMAJ18CA-13-F pinout, SMAJ18CA-13-F application, or SMAJ18CA-13-F equivalent, key selection criteria include clamping voltage margin relative to protected IC VCC, unidirectional vs. bidirectional polarity requirements, IEC 61000-4-2/4-5 compliance headroom, and thermal derating above +25°C ambient.
Technical Context
This bidirectional TVS operates symmetrically across both polarities, enabling protection of AC-coupled or floating signal paths without polarity constraints. Its 1.0mA breakdown test current and 5.0µA max reverse leakage at VRWM ensure low standby power loss in always-on systems.
The device uses a planar junction structure with glass passivation for stable avalanche characteristics and high reliability under repetitive surge stress. Thermal performance is defined by a -55°C to +150°C operating junction temperature range and 1.0W steady-state power dissipation at TL = +75°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power | 400W - Sustains single 10/1000µs waveform surges up to this level without failure |
| Reverse Standoff Voltage (VRWM) | 18V - Maximum continuous DC or RMS voltage before significant leakage begins |
| Clamping Voltage (VC) | 29.2V @ IPP = 13.7A - Limits transient voltage seen by downstream circuitry during surge events |
| Breakdown Voltage (VBR) | 20.0–22.1V @ IT = 1.0mA - Confirms reliable avalanche initiation within specified tolerance band |
| Package | SMA - Surface-mount outline with 4.0–4.6mm body length, compatible with standard reflow profiles |
| Operating Temperature | -55°C to +150°C - Supports under-hood automotive and industrial environments |
Pinout & Package
Two-terminal SMA package with cathode band omitted (bidirectional configuration). Terminals are matte tin-plated for solderability per MIL-STD-202, Method 208. Moisture sensitivity level is J-STD-020 Level 1.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Transient conduction path | Both terminals behave identically; conducts bidirectionally when voltage exceeds ±VBR |
| Case | Non-electrical mechanical interface | Molded plastic housing rated UL 94V-0; no internal connection to silicon die |
Key Features
| Feature | Design Value |
|---|---|
| 400W peak pulse power rating | Enables robust protection against ISO 7637-2 Pulse 1/2a/5a and IEC 61000-4-5 Level 3 surges |
| Glass-passivated die construction | Ensures stable avalanche characteristics and long-term parameter consistency across temperature and life cycles |
| Bidirectional operation | Protects AC signals, differential buses (e.g., RS-485), and floating power domains without polarity dependency |
| RoHS-compliant, halogen-free "Green" design | Meets automotive and industrial environmental compliance mandates including AEC-Q200 alignment |
Applications
| Automotive Infotainment Power Rail | Industrial RS-485 Interface |
|---|---|
Use Scenario: Protecting 12V supply input to head unit MCU and audio codec from load dump and jump-start transients. IC Role / Device Role: Primary clamping element placed upstream of DC-DC converter input. Use Value: Clamps 12V rail to ≤29.2V during 35V/100ms load dump, preventing overvoltage damage to downstream regulators. | Use Scenario: Shielding RS-485 transceiver data lines from ESD and cable-induced surges in factory automation networks. IC Role / Device Role: Bidirectional TVS placed across differential pair (A/B) and ground. Use Value: Limits transient common-mode voltage to <30V, preserving transceiver integrity during ±8kV contact ESD per IEC 61000-4-2. |
| Smart Meter AC Mains Input | Medical Patient Monitoring Sensor Port |
Use Scenario: Safeguarding isolated AC-DC auxiliary supply input against lightning-induced surges on utility-connected meters. IC Role / Device Role: Secondary-level TVS after MOV primary protection, handling residual fast-rising transients. Use Value: Responds in <1ns to clamp sub-microsecond spikes that bypass slower MOV response, reducing stress on optocoupler isolation barrier. | Use Scenario: Protecting analog front-end inputs of ECG/SpO₂ sensors from electrostatic discharge during clinical handling. IC Role / Device Role: Low-capacitance (<100pF) TVS placed directly at connector pins. Use Value: Adds <1pF parasitic capacitance to signal path while suppressing ±15kV air discharge per IEC 61000-4-2 without distorting µV-level biopotential waveforms. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A-13-F | Unidirectional version; same VRWM, VC, and package but asymmetric conduction | Required only where polarity is fixed (e.g., DC power rail with known ground reference) | Select when protecting single-polarity circuits to avoid unnecessary bidirectional leakage path |
| SMBJ18CA | Same electrical specs but SMB package (larger footprint, higher PPK = 600W) | Used where board space allows larger footprint and higher surge margin is needed | Choose for enhanced ruggedness in harsh environments where PCB layout permits 5.3mm × 4.6mm footprint |
Compared with SMAJ18A-13-F, this bidirectional variant eliminates polarity-dependent placement errors but exhibits identical clamping behavior in either direction; versus SMBJ18CA, it trades 50% lower surge rating for 30% smaller PCB area-critical in space-constrained automotive modules.
Availability
SMAJ18CA-13-F is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial communication interfaces, and smart energy metering requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for SMAJ18CA-13-F 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, headquartered in Plano, Texas, with design, manufacturing, and sales operations across Asia, Europe, and North America.
This part belongs to the SMAJ series of transient voltage suppressors engineered specifically for high-reliability overvoltage protection in automotive, industrial, and communications equipment where compact size and repeatable clamping performance are essential.
FAQ
What is the maximum clamping voltage of SMAJ18CA-13-F at its rated peak pulse current?
The maximum clamping voltage (VC) is 29.2V at a peak pulse current (IPP) of 13.7A, measured using the 10/1000µs standard waveform. This value is guaranteed across the full operating temperature range and defines the upper voltage limit imposed on protected circuitry during surge events.
How does the bidirectional configuration affect circuit design compared to unidirectional TVS diodes?
Bidirectional operation eliminates polarity marking and orientation constraints during placement, simplifying assembly and reducing risk of misorientation. It enables protection of AC-coupled or floating nodes (e.g., RS-485, CAN, audio lines) where voltage polarity reverses, unlike unidirectional types that conduct only during negative transients relative to cathode.
Is SMAJ18CA-13-F qualified for automotive applications per AEC-Q200?
No-this standard-grade part is not AEC-Q200 qualified. Diodes offers the automotive-compliant SMAJ18CAQ-13-F variant, manufactured in IATF 16949-certified facilities and qualified to AEC-Q200 Rev D. The standard part meets RoHS and halogen-free requirements but lacks PPAP documentation and extended reliability testing.
What is the thermal derating behavior above +25°C ambient temperature?
Peak pulse power derates linearly from 100% at +25°C to approximately 50% at +100°C, per Figure 1 in DS19005. Steady-state power dissipation drops from 1.0W at TL = +75°C to zero at +150°C, following the curve in Figure 6. Derating must be applied for repeated surge events or elevated ambient conditions.
SMAJ18CA-13-F Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- DO-214AC, SMA
- Series:
- -
- 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):
- 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:
- SMA
SMAJ18CA-13-F FAQ
1.How can I place an order for SMAJ18CA-13-F through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ18CA-13-F 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 SMAJ18CA-13-F reliable?
The price and inventory of SMAJ18CA-13-F are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ18CA-13-F is usually 5 days.
3.What payment methods are accepted for SMAJ18CA-13-F?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ18CA-13-F transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ18CA-13-F?
SMAJ18CA-13-F orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ18CA-13-F 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 SMAJ18CA-13-F?
For technical support, including SMAJ18CA-13-F datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ18CA-13-F requirements.
6.How does Aetrix verify that SMAJ18CA-13-F is sourced from the original manufacturer or authorized distributors?
All SMAJ18CA-13-F 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 SMAJ18CA-13-F meets industry standards.
7.What is the process for return or replacement of SMAJ18CA-13-F?
All SMAJ18CA-13-F units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ18CA-13-F, 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 SMAJ18CA-13-F part is unused and in its original packaging.
Return procedure for SMAJ18CA-13-F:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ18CA-13-F 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
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…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
