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Alpha & Omega Semiconductor Inc. SMDJ43A
- Part No.:
- SMDJ43A
- Manufacturer:
- Alpha & Omega Semiconductor Inc.
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
SMDJ43A.pdf
- Description:
- 1CH 43V UNIDIRECTIONAL 3000W SMD
- Quantity:
- Payment:
- Shipping:
Inventory:9,246
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Product details
Overview
SMDJ43A from Alpha & Omega Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode designed for high-energy surge protection in DC power lines and signal interfaces. It features a 43.0 V reverse stand-off voltage (VRWM), 47.8–52.8 V breakdown voltage (VBR) at 1 mA, 69.4 V maximum clamping voltage at 43.3 A peak pulse current, and 3000 W peak pulse power dissipation on a 10/1000 µs waveform - deployed in industrial motor drives to protect IGBT gate drivers from inductive switching transients.
For engineers reviewing the SMDJ43A datasheet, pinout, applications, or equivalent options, key selection criteria include unidirectional polarity, DO-214AB package compatibility with high-current PCB layouts, clamping performance under repetitive 0.01% duty cycle surges, and thermal resistance (RθJL = 15 °C/W) for sustained operation up to 150 °C junction temperature.
Technical Context
The SMDJ43A operates as a silicon avalanche diode optimized for fast transient suppression, with sub-1 ps response time from 0 V to breakdown. Its glass-passivated junction ensures stable VBR tolerance (±5%) and low temperature coefficient (0.1% × VBR per °C ΔT), enabling predictable clamping across automotive and industrial ambient ranges.
Designed for unidirectional DC line protection, it leverages the DO-214AB (SMC J-bend) package's low-profile geometry and built-in strain relief to withstand mechanical stress during reflow and board flex. Electrical characteristics are validated under JEDEC-standard mounting (8.0 mm × 8.0 mm copper pads), where thermal resistance to lead (15 °C/W) supports reliable power derating above 25 °C ambient.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 43.0 V - Maximum continuous reverse operating voltage before clamping begins; sets DC bus protection threshold. |
| VBR @ IT=1 mA | 47.8–52.8 V - Verified avalanche onset range; ensures consistent turn-on across production lots. |
| VC @ IPPM=43.3 A | 69.4 V - Clamped voltage during 3000 W transient; defines worst-case overvoltage seen by downstream ICs. |
| PPPM (10/1000 µs) | 3000 W - Peak surge energy handling capacity; supports IEC 61000-4-5 Level 4 compliance with proper layout. |
| TJ max | +150 °C - Maximum junction temperature; enables use in enclosed enclosures without forced cooling. |
| RθJL | 15 °C/W - Junction-to-lead thermal resistance; allows accurate power derating when soldered to 8 mm² copper pads. |
| Polarity | Unidirectional - Cathode-band marked; prevents reverse conduction in DC systems requiring polarity-specific protection. |
Pinout & Package
DO-214AB (SMC J-bend) package: molded plastic case with matte tin lead-free plating, JEDEC-compliant outline, and cathode band marking on the banded end. Terminals are solderable per MIL-STD-750 Method 2026.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | DC return path / ground reference | Connected to system ground or low-side rail; carries full surge current during clamping. |
| Cathode | Protected line input / high-side connection | Marked with color band; connects to line being protected (e.g., +48 V DC bus); conducts avalanche current to ground. |
Key Features
| Feature | Design Value |
|---|---|
| Fast response time | <1.0 ps - Enables suppression of ESD and lightning-induced transients before sensitive circuitry reacts. |
| Glass-passivated junction | Stable VBR drift <0.1%/°C - Maintains clamping accuracy over temperature without calibration. |
| MSL1 rating | 260 °C peak reflow compatibility - Supports standard lead-free assembly without moisture-related popcorning. |
| UL 94V-0 flammability | Self-extinguishing plastic housing - Meets safety requirements for enclosed industrial equipment. |
| Built-in strain relief | Reduced mechanical stress at solder joints - Improves long-term reliability in vibration-prone motor control environments. |
Applications
| Industrial Motor Drives | Telecom Power Supplies |
|---|---|
Use Scenario: Protecting IGBT gate driver circuits from inductive kickback during PWM switching in 400 V DC bus inverters. IC Role / Device Role: Unidirectional TVS placed between gate and source to clamp negative-going transients below –20 V. Use Value: Limits gate-source voltage excursion to ≤69.4 V during 3000 W surges, preventing gate oxide rupture in 650 V IGBTs. | Use Scenario: Safeguarding -48 V DC telecom rectifier outputs against load dump and lightning-induced surges. IC Role / Device Role: Primary surge clamp on output rail, upstream of DC/DC converters and monitoring ICs. Use Value: Clamps 10/1000 µs transients to 69.4 V while sustaining 43.3 A peak current, preserving downstream PMIC functionality. |
| Automotive Body Control Modules | Renewable Energy Inverters |
Use Scenario: Suppressing load dump spikes on 12 V battery-fed microcontroller power rails in BCMs. IC Role / Device Role: Line-referenced TVS on VCC input of CAN transceivers and LIN interface ICs. Use Value: Withstands ISO 16750-2 Pulse 5a (120 V, 400 ms) via thermal mass and 150 °C TJ rating, avoiding latch-up. | Use Scenario: Protecting MPPT controller inputs from grid-switching transients in solar string combiner boxes. IC Role / Device Role: DC-link surge protector on PV+ and PV− terminals prior to isolation amplifiers. Use Value: Handles repetitive 0.01% duty cycle surges per IEC 61000-4-5, maintaining clamping stability across 25-year field life. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SAC43 | Same VRWM (43 V) and PPPM (3000 W), but TO-220AC package; RθJA = 35 °C/W vs. SMDJ43A's 75 °C/W. | Through-hole mounting only; unsuitable for high-density SMT layouts or automated assembly. | Select SAC43 only when higher thermal mass is needed for infrequent, high-energy events and board space permits through-hole placement. |
| 1.5KE43A | Same electrical specs (VRWM = 43 V, VBR = 47.8–52.8 V), but DO-201AD package; lower IPPM (43.3 A) due to larger RθJA (100 °C/W). | Larger footprint and lower surge current rating limit use in compact, high-power designs. | Choose 1.5KE43A only for legacy through-hole designs or cost-sensitive applications where DO-201AD is already standardized. |
Compared with SAC43 and 1.5KE43A, the SMDJ43A delivers identical surge protection performance in a surface-mount DO-214AB package optimized for automated assembly, thermal efficiency on copper pads, and space-constrained industrial PCBs - making it the preferred choice for new SMT-based power electronics designs.
Availability
SMDJ43A is available at Aetrix Electronics and suitable for industrial motor drives, telecom power supplies, automotive body control modules, and renewable energy inverters requiring stable component supply, RoHS-compliant packaging, and verified surge immunity.
Supply support for SMDJ43A 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
Alpha & Omega Semiconductor (AOS) is a fabless power semiconductor company specializing in high-efficiency MOSFETs, TVS diodes, and power ICs for industrial, computing, and automotive markets.
The SMDJ series is engineered for robust transient suppression in high-power DC systems, with emphasis on tight VBR tolerance, low clamping ratio, and JEDEC-qualified SMT reliability - targeting designers of motor controllers, telecom infrastructure, and renewable energy converters.
FAQ
What is the maximum clamping voltage of the SMDJ43A under a 3000 W transient?
The SMDJ43A has a maximum clamping voltage (VC) of 69.4 V when subjected to its rated peak pulse current of 43.3 A on a 10/1000 µs waveform. This value is measured per the conditions specified in the AOS datasheet Rev. 1.2 (July 2021), with the device mounted on 8.0 mm × 8.0 mm copper pads. The SMDJ43A maintains this clamping performance consistently across its operational temperature range.
Does the SMDJ43A support bidirectional surge protection?
No, the SMDJ43A is a unidirectional TVS diode, indicated by the "A" suffix and cathode band marking. For bidirectional operation, the SMDJ43CA variant must be used. The SMDJ43A conducts only during reverse overvoltage events and blocks forward current beyond its rated IFSM of 300 A (8.3 ms half-sine), making it suitable for DC line protection where polarity is fixed.
What is the thermal resistance from junction to ambient for the SMDJ43A?
The typical thermal resistance from junction to ambient (RθJA) for the SMDJ43A is 75 °C/W, measured under standard JEDEC conditions (mounted on 8.0 mm × 8.0 mm copper pads). This value assumes natural convection and is used to calculate safe steady-state power dissipation limits. For more accurate thermal modeling, the junction-to-lead resistance (RθJL = 15 °C/W) should be applied when heatsinking via PCB copper is employed.
Is the SMDJ43A compliant with lead-free assembly standards?
Yes, the SMDJ43A features matte tin lead-free plating and is qualified for MSL Level 1 per J-STD-020, with a maximum peak reflow temperature of 260 °C. It meets RoHS and AOS Green Policy requirements (halogen-free, Pb-free), and is compatible with standard lead-free soldering profiles used in industrial electronics manufacturing.
How does the SMDJ43A compare to the older P6SMB43A in terms of surge capability?
The SMDJ43A provides 3000 W peak pulse power (PPPM) on a 10/1000 µs waveform, whereas the P6SMB43A is rated for 600 W - meaning the SMDJ43A delivers five times higher surge energy handling. Both share similar VRWM (43 V) and VBR (47.8–52.8 V), but the SMDJ43A's DO-214AB package offers superior thermal performance and SMT compatibility versus the P6SMB43A's DO-214AA outline.
SMDJ43A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Alpha & Omega Semiconductor Inc.
- Package/Case:
- DO-214AB, SMC
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 43V
- Voltage - Breakdown (Min):
- 47.8V
- Voltage - Clamping (Max) @ Ipp:
- 69.4V
- Current - Peak Pulse (10/1000µs):
- 43.3A
- Power - Peak Pulse:
- 3000W (3kW)
- 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-214AB
SMDJ43A FAQ
1.How can I place an order for SMDJ43A through Aetrix?
Please submit a Request for Quotation (RFQ) for SMDJ43A 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 SMDJ43A reliable?
The price and inventory of SMDJ43A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMDJ43A is usually 5 days.
3.What payment methods are accepted for SMDJ43A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMDJ43A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMDJ43A?
SMDJ43A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMDJ43A 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 SMDJ43A?
For technical support, including SMDJ43A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMDJ43A requirements.
6.How does Aetrix verify that SMDJ43A is sourced from the original manufacturer or authorized distributors?
All SMDJ43A 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 SMDJ43A meets industry standards.
7.What is the process for return or replacement of SMDJ43A?
All SMDJ43A units undergo pre-shipment inspection (PSI). If there is an issue with SMDJ43A, 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 SMDJ43A part is unused and in its original packaging.
Return procedure for SMDJ43A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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