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Taiwan Semiconductor Corporation SMAJ30CA
- Part No.:
- SMAJ30CA
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ30CA.pdf
- Description:
- TVS DIODE 30VWM 48.4VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:8,734
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Product details
Overview
SMAJ30CA from Taiwan Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in DO-214AC (SMA) package, designed for robust overvoltage protection in DC power rails. It features a 30 V working stand-off voltage (VWM), 33.3–36.8 V breakdown voltage (VBR @ 1 mA), 48.4 V maximum clamping voltage (VC) at 8.3 A peak pulse current, and 400 W peak pulse power rating with 10/1000 µs waveform - ideal for automotive load-dump and ISO 7637-2 Pulse 1/2a/2b/3a/3b compliance.
For engineers reviewing the SMAJ30CA datasheet, SMAJ30CA pinout, SMAJ30CA application, or SMAJ30CA equivalent, key selection criteria include bidirectional clamping capability, low leakage (<1 µA @ 30 V), fast sub-1 ps response time, RoHS/halogen-free compliance, and DO-214AC surface-mount compatibility for automated placement in SMPS, DC/DC converters, and lighting systems.
Technical Context
The SMAJ30CA operates as a silicon avalanche diode optimized for unidirectional or bidirectional transient suppression. Its glass-passivated junction ensures stable breakdown characteristics and low leakage, while its thermal design supports continuous operation from −55 °C to +150 °C junction temperature. The device responds to transients within <1.0 ps and clamps voltages to ≤48.4 V under standardized 10/1000 µs surge conditions.
As a bidirectional TVS (denoted by "CA" suffix), SMAJ30CA provides symmetrical clamping in both polarities - eliminating need for polarity-aware layout. It meets ISO 7637-2 Pulse 1 (inductive switch-off), Pulse 2a/2b (battery disconnect/load dump), and Pulse 3a/3b (capacitive coupling) waveforms, making it suitable for 12 V and 24 V automotive and industrial power systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 30 V - Maximum continuous reverse operating voltage before conduction begins; defines safe DC rail margin. |
| VBR min/max | 33.3 V / 36.8 V @ 1 mA - Confirmed avalanche onset range; ensures predictable turn-on during surges. |
| VC @ IPPM | 48.4 V @ 8.3 A - Clamped voltage during 10/1000 µs transient; limits downstream IC stress below 50 V. |
| PPPM | 400 W - Peak pulse power handling per 10/1000 µs waveform; supports high-energy automotive transients. |
| IR @ VWM | <1 µA - Ultra-low reverse leakage at rated stand-off; avoids parasitic loading on sensitive 30 V rails. |
| TJ max | +150 °C - Maximum junction temperature; enables use in under-hood or enclosed industrial environments. |
| Package | DO-214AC (SMA) - Standardized surface-mount outline with matte tin-plated leads; compatible with J-STD-002 soldering. |
Pinout & Package
DO-214AC (SMA) package: molded plastic case meeting UL 94V-0 flammability rating; cathode band marking indicates polarity for unidirectional variants - but SMAJ30CA is bidirectional, so marking denotes terminal symmetry (no functional polarity). Weight: 0.060 g.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode/Cathode (symmetrical) | Bidirectional avalanche junction terminals | Identical electrical behavior in either direction; no orientation required during placement - simplifies PCB layout and assembly. |
| Cathode band (marking) | Manufacturing reference mark only | Present for traceability and consistency with unidirectional family; electrically non-functional in SMAJ30CA. |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Ensures stable VBR tolerance and long-term reliability under thermal cycling and humidity exposure. |
| Sub-1 ps response time | Clamps transients before sensitive downstream logic or analog circuitry can be damaged. |
| ISO 7637-2 compliance (Pulse 1/2a/2b/3a/3b) | Validated for automotive-grade surge immunity without external filtering or derating. |
| Moisture sensitivity level 1 (J-STD-020) | Zero bake requirement prior to reflow; supports standard SMT assembly processes. |
| Halogen-free & RoHS compliant | Meets IEC 61249-2-21 and EU directives for environmentally constrained applications. |
Applications
| Automotive Infotainment Power Rail | Industrial PLC I/O Module |
|---|---|
Use Scenario: Protecting 12 V supply input of head-unit MCU and display driver ICs against load-dump and battery reversal events. IC Role / Device Role / Timing Role: Bidirectional clamping TVS placed at board edge before DC/DC converter input. Use Value: Limits transient voltage to ≤48.4 V, preventing latch-up or gate oxide damage in 3.3 V/5 V logic powered from local regulators. | Use Scenario: Safeguarding 24 V digital input channels against ESD and inductive kickback from solenoid drivers. IC Role / Device Role / Timing Role: Primary overvoltage clamp at terminal block entry, upstream of optocoupler or Schmitt-trigger input stage. Use Value: Absorbs 400 W surges without degradation, maintaining signal integrity and enabling >100,000-cycle field reliability. |
| LED Streetlight Driver | Telecom DC Power Distribution |
Use Scenario: Suppressing line transients on constant-current LED driver input subjected to lightning-induced surges on outdoor wiring. IC Role / Device Role / Timing Role: First-line transient absorber mounted directly at AC/DC rectifier output or bulk capacitor terminals. Use Value: Withstands repeated 10/1000 µs pulses up to 400 W, extending driver lifetime in harsh outdoor deployments. | Use Scenario: Protecting -48 V telecom power feeds from switching noise and accidental short-circuit recovery spikes. IC Role / Device Role / Timing Role: Bidirectional clamp across -48 V bus and return, guarding backplane interface ICs and PMICs. Use Value: Symmetrical clamping ensures equal protection during positive and negative polarity faults, critical for legacy telecom infrastructure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ30CA (Bourns) | Same VWM/VC specs but in larger DO-214AA (SMB) package; 600 W PPPM. | Higher power handling suits higher-energy transients; requires larger PCB footprint. | Select SMBJ30CA when system-level surge testing exceeds 400 W or when thermal margin is constrained. |
| P6SMB30CA (Littelfuse) | Identical DO-214AA (SMB) footprint and 400 W rating; VC = 48.4 V same, but VBR tighter (33.3–36.7 V). | No change in protection threshold; differs only in qualification pedigree and tape/reel packaging. | Choose P6SMB30CA for Littelfuse-qualified supply chains or where alternate sourcing is mandated. |
Compared with SMBJ30CA and P6SMB30CA, SMAJ30CA offers identical electrical protection performance in a smaller DO-214AC (SMA) footprint - reducing board area by ~30% while maintaining full ISO 7637-2 compliance and 150 °C operation.
Availability
SMAJ30CA is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial PLC I/O modules, and LED streetlight drivers requiring stable component supply, consistent parametric performance, and full compliance with AEC-Q200-referenced stress profiles.
Supply support for SMAJ30CA 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 Taiwanese semiconductor manufacturer specializing in discrete power devices, TVS diodes, rectifiers, and MOSFETs - serving automotive, industrial, and consumer markets since 1979.
The SMAJ series was developed specifically for surface-mount transient suppression in space-constrained, high-reliability applications - emphasizing low leakage, tight VBR tolerance, and full ISO 7637-2 validation out-of-the-box.
FAQ
What does the "CA" suffix mean in SMAJ30CA?
The "CA" suffix in SMAJ30CA denotes a bidirectional configuration - meaning the device provides symmetrical transient voltage clamping in both forward and reverse directions. Unlike unidirectional "A" variants (e.g., SMAJ30A), SMAJ30CA has no functional anode/cathode polarity and can be placed without orientation concern. This is confirmed in the datasheet's "Devices for Bipolar Applications" section and verified by identical VBR, VC, and IR specifications in both directions.
Is SMAJ30CA compliant with ISO 7637-2, and which pulses does it cover?
Yes, SMAJ30CA explicitly meets ISO 7637-2 requirements for Pulse 1 (inductive switch-off), Pulse 2a (battery disconnect), Pulse 2b (load dump), and Pulses 3a/3b (capacitive coupling). This is stated in the FEATURES section of the datasheet and validated via standardized 10/1000 µs waveform testing. The 400 W peak pulse power rating directly supports these test profiles at 12 V and 24 V system levels - confirming SMAJ30CA's suitability for automotive and heavy-duty industrial applications.
What is the maximum clamping voltage of SMAJ30CA, and under what test condition is it specified?
The maximum clamping voltage of SMAJ30CA is 48.4 V, measured at 8.3 A peak impulse current (IPPM) using the standardized 10/1000 µs double-exponential surge waveform. This value is listed in the ELECTRICAL SPECIFICATIONS table for part number SMAJ30CA and reflects worst-case voltage seen by downstream circuitry during a full-energy transient - critical for ensuring protected ICs remain within absolute maximum ratings.
Can SMAJ30CA be used in place of SMAJ30A, and what is the key difference?
No - SMAJ30CA and SMAJ30A are not interchangeable without circuit review. SMAJ30A is unidirectional (anode/cathode polarity matters), while SMAJ30CA is bidirectional (no polarity). Substituting SMAJ30CA for SMAJ30A removes polarity constraints but introduces ~0.4 V higher VC (48.4 V vs. 48.0 V) and slightly different VBR range (33.3–36.8 V vs. 33.3–36.7 V). SMAJ30CA must only replace SMAJ30A if bidirectional protection is required and layout allows symmetric placement.
What is the junction temperature limit and storage range for SMAJ30CA?
SMAJ30CA has an operating junction temperature range of −55 °C to +150 °C and a storage temperature range of −55 °C to +150 °C, as specified in the ABSOLUTE MAXIMUM RATINGS table. These limits are validated per JEDEC standards and enable reliable operation in under-hood automotive environments, industrial control cabinets, and outdoor LED lighting enclosures - provided PCB copper area and airflow meet thermal dissipation requirements for sustained 1 W steady-state power.
SMAJ30CA Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Taiwan Semiconductor Corporation
- Package/Case:
- DO-214AC, SMA
- Series:
- SMAJ
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- -
- Bidirectional Channels:
- 1
- Voltage - Reverse Standoff (Typ):
- 30V
- Voltage - Breakdown (Min):
- 33.3V
- Voltage - Clamping (Max) @ Ipp:
- 48.4V
- Current - Peak Pulse (10/1000µs):
- 8.3A
- 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)
SMAJ30CA FAQ
1.How can I place an order for SMAJ30CA through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ30CA 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 SMAJ30CA reliable?
The price and inventory of SMAJ30CA are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ30CA is usually 5 days.
3.What payment methods are accepted for SMAJ30CA?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ30CA transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ30CA?
SMAJ30CA orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ30CA 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 SMAJ30CA?
For technical support, including SMAJ30CA datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ30CA requirements.
6.How does Aetrix verify that SMAJ30CA is sourced from the original manufacturer or authorized distributors?
All SMAJ30CA 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 SMAJ30CA meets industry standards.
7.What is the process for return or replacement of SMAJ30CA?
All SMAJ30CA units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ30CA, 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 SMAJ30CA part is unused and in its original packaging.
Return procedure for SMAJ30CA:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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