My Inquiry
My Account
Taiwan Semiconductor Corporation SMAJ64A
- Part No.:
- SMAJ64A
- Manufacturer:
- Taiwan Semiconductor Corporation
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
SMAJ64A.pdf
- Description:
- TVS DIODE 64VWM 103VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:7,500
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMAJ64A from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in DO-214AC (SMA) package, designed for clamping fast transients on DC power lines. It features a 64 V working stand-off voltage (VWM), 71.1–78.6 V breakdown voltage (VBR), and clamps to ≤103 V at 3.9 A peak impulse current under 10/1000 µs waveform - used in automotive power rail protection and industrial DC/DC converters.
For engineers reviewing the SMAJ64A datasheet, SMAJ64A pinout, SMAJ64A application, or SMAJ64A equivalent, key selection criteria include clamping voltage margin relative to system overvoltage tolerance, leakage current (<1 µA at 64 V), thermal derating above 25°C, and compliance with ISO 7637-2 Pulse 1/2a/2b/3a/3b for automotive electronics.
Technical Context
The SMAJ64A operates as a unidirectional avalanche diode with glass-passivated junction, optimized for sub-nanosecond response (<1.0 ps from 0 V to VBR min). Its clamping action begins at VBR and sustains 400 W peak pulse power (10/1000 µs) up to 25°C, derating linearly above that ambient per Fig.2.
It supports single-die configuration in DO-214AC package with cathode band polarity marking, matte tin-plated leads compliant with J-STD-002 solderability, and meets JESD201 Class 2 whisker resistance and UL 94V-0 flammability requirements.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 64 V - maximum continuous reverse operating voltage before significant leakage |
| VBR @ IT=1 mA | 71.1–78.6 V - guaranteed avalanche initiation range defining turn-on threshold |
| VC @ IPPM=3.9 A | ≤103 V - clamped voltage during 10/1000 µs surge, limiting downstream IC stress |
| IR @ VWM | <1 µA - minimal standby power loss and signal integrity impact in high-impedance circuits |
| PPPM | 400 W (10/1000 µs) - surge energy handling capacity for automotive load dump and inductive switching events |
| TJ max | 150 °C - maximum junction temperature enabling operation in under-hood or enclosed industrial environments |
| Package | DO-214AC (SMA) - industry-standard surface-mount outline with 0.060 g mass and J-STD-020 Level 1 moisture sensitivity |
Pinout & Package
DO-214AC (SMA) package: molded plastic case with cathode band marking; anode and cathode terminals aligned along body axis; lead finish: matte tin; compliant with RoHS and halogen-free (IEC 61249-2-21).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode (unmarked end) | Current entry point in forward bias; connected to lower-potential side of protected line | Enables standard orientation for unidirectional clamping from VCC to GND or signal-to-rail |
| Cathode (banded end) | Current exit point in forward bias; connected to higher-potential side (e.g., VCC) | Defines polarity-sensitive placement - reversal causes open-circuit behavior during reverse transients |
Key Features
| Feature | Design Value |
|---|---|
| Glass-passivated junction | Ensures stable VBR and low leakage across temperature and lifetime, critical for automotive reliability |
| Fast response time <1.0 ps | Clamps ESD and fast-edge transients before sensitive logic or analog circuitry responds |
| ISO 7637-2 compliance (Pulse 1/2a/2b/3a/3b) | Validated for automotive battery-line surge immunity without external filtering redesign |
| Moisture sensitivity Level 1 | Eliminates bake-out requirement prior to reflow, reducing manufacturing cost and process risk |
| UL 94V-0 molding compound | Meets flame-retardancy requirements for enclosed power supplies and lighting systems |
Applications
| Automotive Power Rail Protection | Industrial DC/DC Converter Input |
|---|---|
Use Scenario: Protecting microcontroller power inputs against load dump (ISO 7637-2 Pulse 5a) and alternator ripple in 12 V/24 V vehicle systems. IC Role / Device Role / Timing Role: Unidirectional TVS clamping transient overvoltage between battery rail and ground. Use Value: Limits VCC spikes to ≤103 V, preserving 15 V-rated LDOs and MCU IO tolerances without derating. | Use Scenario: Safeguarding isolated DC/DC converter primary-side input against inductive kickback from relay coils or motor drivers. IC Role / Device Role / Timing Role: Standoff-clamp TVS placed upstream of input filter capacitor to absorb 400 W surges. Use Value: Prevents input-stage MOSFET avalanche failure and maintains regulation during 10/1000 µs transients. |
| LED Driver Power Stage | Telecom Power Interface |
Use Scenario: Shielding constant-current LED driver ICs from supply-line transients in streetlight or architectural lighting fixtures. IC Role / Device Role / Timing Role: Primary overvoltage clamp on 48 V bus feeding buck controller and gate drivers. Use Value: Maintains <1 µA leakage at 48 V nominal, avoiding false triggering while clamping to ≤103 V during lightning-induced surges. | Use Scenario: Front-end surge suppression on -48 V telecom power feed entering remote radio units or base station controllers. IC Role / Device Role / Timing Role: Unidirectional clamping device referenced to negative rail, absorbing positive-going transients. Use Value: Withstands repeated 400 W pulses without degradation, meeting GR-1089-CORE Level 3 surge immunity requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ64 | Higher clamping voltage (114 V vs. 103 V at same IPPM); wider VBR range (71.1–86.9 V) | Less margin for 64 V systems near absolute maximum ratings; requires verification of downstream voltage tolerance | Select SMAJ64 only if clamping voltage margin allows ≥114 V peak exposure |
| SMBJ64A | Same VWM/VBR/VC specs but in larger DO-214AA (SMB) package; 600 W PPPM | Higher surge rating suits higher-energy environments; requires PCB pad revision due to larger footprint | Choose SMBJ64A when system-level surge testing exceeds 400 W or thermal dissipation demands larger package |
Compared with SMAJ64 and SMBJ64A, the SMAJ64A offers optimal balance of compact DO-214AC footprint, tight 103 V clamping, and verified ISO 7637-2 compliance - making it preferred for space-constrained automotive and industrial modules where layout change is not feasible.
Availability
SMAJ64A is available at Aetrix Electronics and suitable for automotive power rail protection, industrial DC/DC converter input stages, and LED driver power stage designs requiring stable component supply and full traceability.
Supply support for SMAJ64A 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 automotive, industrial, and consumer markets.
The SMAJ series is part of TSC's transient voltage suppressor product line, engineered specifically for robust, surface-mount surge protection in harsh environments including automotive electronics and industrial power systems.
FAQ
What is the clamping voltage of SMAJ64A and how is it measured?
The SMAJ64A has a maximum clamping voltage (VC) of 103 V, measured at a peak impulse current (IPPM) of 3.9 A using the standardized 10/1000 µs double-exponential surge waveform. This value is guaranteed across production lots and validated per JEDEC test methods. The SMAJ64A achieves this clamping performance while maintaining <1 µA leakage at its 64 V working stand-off voltage, ensuring minimal impact on normal operation.
Is SMAJ64A unidirectional or bidirectional, and how is polarity identified?
SMAJ64A is a unidirectional TVS diode, intended for clamping transients between a positive rail and ground. Polarity is marked by a cathode band on the DO-214AC (SMA) package - the banded end connects to the higher-potential node (e.g., VCC), and the unmarked end is the anode (ground side). Bidirectional variants use "CA" suffix (e.g., SMAJ64CA), which SMAJ64A does not carry.
Does SMAJ64A meet automotive surge immunity standards?
Yes, SMAJ64A meets ISO 7637-2 requirements for Pulse 1 (inductive load disconnect), Pulse 2a (sudden load removal), Pulse 2b (supply interruption), Pulse 3a (capacitive coupled transients), and Pulse 3b (ground noise). Its 400 W peak pulse power rating and sub-nanosecond response enable direct integration into automotive ECUs, body control modules, and lighting controllers without additional filtering components.
What is the maximum operating temperature for SMAJ64A?
The SMAJ64A has a maximum junction temperature (TJ) of 150 °C and an operating junction temperature range of –55 °C to +150 °C. Its thermal performance is characterized with derating curves (Fig.2 in the datasheet), allowing reliable operation in under-hood automotive environments and enclosed industrial enclosures where ambient temperatures exceed 85 °C.
How does SMAJ64A compare to SMAJ64 in terms of clamping performance?
SMAJ64A clamps to ≤103 V at 3.9 A, whereas SMAJ64 clamps to ≤114 V at the same current. This 11 V difference provides tighter overvoltage protection for 64 V systems, especially those with narrow voltage margins such as automotive 48 V mild-hybrid architectures. Both share identical VWM (64 V) and package (DO-214AC), but SMAJ64A's tighter VBR range (71.1–78.6 V vs. 71.1–86.9 V) enables more predictable turn-on behavior.
SMAJ64A 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:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 64V
- Voltage - Breakdown (Min):
- 71.1V
- Voltage - Clamping (Max) @ Ipp:
- 103V
- Current - Peak Pulse (10/1000µs):
- 3.9A
- 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)
SMAJ64A FAQ
1.How can I place an order for SMAJ64A through Aetrix?
Please submit a Request for Quotation (RFQ) for SMAJ64A 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 SMAJ64A reliable?
The price and inventory of SMAJ64A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMAJ64A is usually 5 days.
3.What payment methods are accepted for SMAJ64A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMAJ64A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMAJ64A?
SMAJ64A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMAJ64A 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 SMAJ64A?
For technical support, including SMAJ64A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMAJ64A requirements.
6.How does Aetrix verify that SMAJ64A is sourced from the original manufacturer or authorized distributors?
All SMAJ64A 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 SMAJ64A meets industry standards.
7.What is the process for return or replacement of SMAJ64A?
All SMAJ64A units undergo pre-shipment inspection (PSI). If there is an issue with SMAJ64A, 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 SMAJ64A part is unused and in its original packaging.
Return procedure for SMAJ64A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMAJ64A 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…
