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onsemi 1.5SMC56AT3
- Part No.:
- 1.5SMC56AT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AB, SMC
- Datasheet:
-
1.5SMC56AT3.pdf
- Description:
- TVS DIODE 47.8VWM 77VC SMC
- Quantity:
- Payment:
- Shipping:
Inventory:4,142
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Product details
Overview
1.5SMC56AT3 from ON Semiconductor is a unidirectional 1500 W peak power Zener transient voltage suppressor (TVS) designed for parallel overvoltage protection of DC power rails and signal lines. It features a 47.8 V minimum breakdown voltage at 1 mA, 56 V nominal Zener voltage, 77 V maximum clamping voltage at 19.5 A peak pulse current, and <5 µA reverse leakage above 47.8 V - used in industrial power supplies, automotive ECUs, and telecom interface protection.
For engineers reviewing the 1.5SMC56AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include working peak reverse voltage (47.8 V), clamping performance under 1 ms surge, UL 497B recognition for isolated loop circuits, and SMC surface-mount package compatibility with high-energy transient immunity requirements.
Technical Context
The 1.5SMC56AT3 operates as a unidirectional Zener-based TVS diode, conducting only in reverse bias above its breakdown threshold to clamp transients. Its design relies on avalanche breakdown physics with specified temperature coefficient (0.103 %/°C) and fast response time (<1 ns), enabling protection against ESD (Class 3, >16 kV HBM) and lightning-induced surges.
It is rated for 1500 W non-repetitive peak pulse power (10/1000 µs waveform), with thermal derating starting at 75°C junction temperature. The device uses a void-free Surmetic™ thermoset plastic SMC package with modified L-bend leads and cathode polarity notch - optimized for high-surge reliability without bond wire limitations.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power | 1500 W @ 1 ms (10/1000 µs waveform); sustains single high-energy surges common in automotive load-dump or telecom lightning events |
| Working Peak Reverse Voltage (VRWM) | 47.8 V; maximum continuous DC or peak AC voltage the device blocks before clamping begins |
| Zener Breakdown Voltage (VBR) | 53.2–58.8 V @ 1 mA; tight tolerance ensures predictable turn-on during overvoltage events |
| Clamping Voltage (VC) | 77 V @ 19.5 A IPP; defines worst-case voltage seen by protected circuit during full-rated surge |
| Reverse Leakage Current | <5 µA @ 47.8 V; negligible standby power loss and minimal impact on high-impedance sensing nodes |
| Response Time | <1 ns; enables effective suppression of fast-rising ESD and switching noise transients |
| ESD Rating | Class 3 (>16 kV) per Human Body Model; qualifies for IEC 61000-4-2 Level 4 system-level ESD immunity |
Pinout & Package
1.5SMC56AT3 is housed in an SMC (DO-214AB) surface-mount package (Case 403), measuring 7.75 × 6.60 × 2.41 mm, with cathode indicated by a molded notch and modified L-bend leads for enhanced solder joint reliability.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / low-side reference | Connected to ground or lowest potential node in unidirectional configuration; carries surge current to reference plane |
| Cathode | Reverse-biased Zener terminal / high-side connection | Connected to protected line (e.g., 48 V rail); avalanche conduction initiates here during overvoltage |
Key Features
| Feature | Design Value |
|---|---|
| UL 497B Recognition | Qualified for isolated loop circuit protection - meets stringent strike voltage, endurance, and dielectric withstand requirements for telecom and industrial safety compliance |
| Low Clamping Ratio | VC/VBR ≈ 1.45 (77 V / 53.2 V); minimizes overvoltage stress on downstream ICs compared to higher-ratio suppressors |
| High Surge Current Capacity | 19.5 A peak pulse current (IPP); supports robust protection in 24–48 V systems exposed to ISO 7637-2 Pulse 1/2/5a |
| Thermal Robustness | RJL = 54.6 °C/W (junction-to-lead); enables efficient heat transfer to PCB copper, supporting repeated surge handling in confined layouts |
| Polarity Identification | Molded cathode notch + marking "56A" on body; eliminates assembly errors in automated SMT placement |
Applications
| Industrial Power Supply Protection | Automotive Body Control Module (BCM) |
|---|---|
|
Use Scenario: 48 V auxiliary power rail in programmable logic controller (PLC) power input stage exposed to inductive kickback and hot-swap transients. IC Role / Device Role / Timing Role: Unidirectional TVS placed across input terminals to clamp surges before they reach upstream DC/DC converter and microcontroller. Use Value: Limits transient voltage to ≤77 V, preventing damage to 60 V-rated input capacitors and enabling reliable operation per IEC 61000-4-4 Level 3. |
Use Scenario: LIN bus line protection in BCM where 12 V supply and communication lines coexist on shared PCB layers. IC Role / Device Role / Timing Role: Parallel-connected TVS on LIN data line referenced to chassis ground, suppressing coupled transients from solenoid drivers. Use Value: Sub-1 ns response prevents data corruption during ESD events; low capacitance avoids signal integrity degradation at 20 kbps LIN rates. |
| Telecom Remote Power Feeding | Medical Imaging Sensor Interface |
|
Use Scenario: 48 V phantom power feed to remote IP cameras over PoE-like cabling, subject to lightning-induced longitudinal surges. IC Role / Device Role / Timing Role: Primary overvoltage clamp on DC input side of isolation barrier, coordinated with secondary-side TVS and gas discharge tube. Use Value: UL 497B certification validates suitability for isolated loop protection; 1500 W rating handles multi-kA surge currents per ITU-T K.21 Basic Level. |
Use Scenario: Analog front-end protection for X-ray detector ASICs receiving low-level signals from scintillation sensors. IC Role / Device Role / Timing Role: Low-leakage (≤5 µA) TVS on sensor bias rail to prevent baseline shift while maintaining signal-to-noise ratio. Use Value: Tight VBR tolerance (±5%) ensures consistent clamping without false triggering; stable temperature coefficient avoids drift across 0–50°C operating range. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ56A | Same 56 V nominal VBR but lower 600 W peak power rating and SMB package (smaller thermal mass) | Limited to lower-energy transients (e.g., IEC 61000-4-2 ±8 kV contact); unsuitable for ISO 7637-2 Pulse 5a | Select when board space is constrained and surge energy does not exceed 600 W capability |
| 1.5KE56A | Through-hole DO-201 package, identical electrical specs but no UL 497B recognition and slower thermal response | Not certified for isolated loop protection; requires manual assembly and larger PCB footprint | Choose only for legacy through-hole designs where UL certification is not required |
Compared with SMBJ56A and 1.5KE56A, the 1.5SMC56AT3 delivers superior surge handling (1500 W vs. 600 W or 1500 W with inferior thermal path), surface-mount scalability, and UL 497B validation - making it the preferred choice for new industrial and automotive designs requiring certified, high-reliability transient suppression.
Availability
1.5SMC56AT3 is available at Aetrix Electronics and suitable for industrial power supplies, automotive electronic control units, and telecom remote powering systems requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for 1.5SMC56AT3 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
ON Semiconductor (now onsemi) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and medical markets.
The 1.5SMC56AT3 belongs to the SMC-series transient voltage suppressors - engineered for high-surge immunity in surface-mount applications where reliability, UL certification, and compact size are critical for modern power and interface protection.
FAQ
What is the clamping voltage of the 1.5SMC56AT3 at its rated peak pulse current?
The 1.5SMC56AT3 has a maximum clamping voltage (VC) of 77 V at its rated peak pulse current (IPP) of 19.5 A, measured using a 10/1000 µs waveform. This value defines the upper voltage limit imposed on the protected circuit during a full-rated transient event and is confirmed in the official ON Semiconductor datasheet Table on page 3. The 1.5SMC56AT3 maintains this clamping performance across its qualified operating temperature range.
Is the 1.5SMC56AT3 certified for UL 497B isolated loop protection?
Yes, the 1.5SMC56AT3 is UL Recognized under file #116110 for classification QVGV2 per UL 497B - specifically validating its use in isolated loop circuits such as telecom interfaces and industrial fieldbus systems. This certification covers multiple tests including strike voltage breakdown, endurance conditioning, and dielectric withstand. The 1.5SMC56AT3 achieves this as part of the fully recognized 1.5SMC6.8AT3 series.
What is the working peak reverse voltage (VRWM) specification for the 1.5SMC56AT3?
The 1.5SMC56AT3 has a working peak reverse voltage (VRWM) of 47.8 V, meaning it reliably blocks voltages up to this level in normal operation while remaining below its Zener breakdown threshold. This parameter is critical for selecting the correct TVS for a given DC rail - for example, it is suitable for 48 V systems where continuous operating voltage must stay below VRWM to avoid leakage or premature conduction. The 1.5SMC56AT3's VRWM is defined at 25°C and derates predictably with temperature.
Does the 1.5SMC56AT3 meet ESD immunity standards?
Yes, the 1.5SMC56AT3 is rated for Class 3 ESD immunity (>16 kV) per the Human Body Model (HBM), as stated in its specification features. This makes it suitable for protecting sensitive inputs against electrostatic discharge in manufacturing, handling, and end-use environments. The 1.5SMC56AT3 achieves this performance via low-junction-capacitance Zener structure and fast avalanche response - verified in ON Semiconductor's characterization testing.
What package type and mounting style does the 1.5SMC56AT3 use?
The 1.5SMC56AT3 uses the SMC (DO-214AB) surface-mount package (Case 403), with dimensions of 7.75 × 6.60 × 2.41 mm and modified L-bend leads for improved solder joint strength. It is supplied on 13-inch tape-and-reel (2500 units per reel) and designed for reflow soldering at 260°C for 10 seconds. The cathode is marked by a molded notch - a key identification feature for correct orientation during automated placement of the 1.5SMC56AT3.
1.5SMC56AT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AB, SMC
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 47.8V
- Voltage - Breakdown (Min):
- 53.2V
- Voltage - Clamping (Max) @ Ipp:
- 77V
- Current - Peak Pulse (10/1000µs):
- 19.5A
- Power - Peak Pulse:
- 1500W (1.5kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMC
1.5SMC56AT3 FAQ
1.How can I place an order for 1.5SMC56AT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1.5SMC56AT3 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 1.5SMC56AT3 reliable?
The price and inventory of 1.5SMC56AT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1.5SMC56AT3 is usually 5 days.
3.What payment methods are accepted for 1.5SMC56AT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1.5SMC56AT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1.5SMC56AT3?
1.5SMC56AT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1.5SMC56AT3 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 1.5SMC56AT3?
For technical support, including 1.5SMC56AT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1.5SMC56AT3 requirements.
6.How does Aetrix verify that 1.5SMC56AT3 is sourced from the original manufacturer or authorized distributors?
All 1.5SMC56AT3 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 1.5SMC56AT3 meets industry standards.
7.What is the process for return or replacement of 1.5SMC56AT3?
All 1.5SMC56AT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1.5SMC56AT3, 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 1.5SMC56AT3 part is unused and in its original packaging.
Return procedure for 1.5SMC56AT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1.5SMC56AT3 Tags
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ESD9B5.0ST5G
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DESD3V3E1BL-7B
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Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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DESD5V0U1BB-7
Diodes Incorporated
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Diodes Incorporated
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Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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