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onsemi 1SMC30AT3
- Part No.:
- 1SMC30AT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- -
- Datasheet:
-
1SMC30AT3.pdf
- Description:
- TVS 1500W 30V UNIDIRECT SMC
- Quantity:
- Payment:
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Inventory:5,503
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Product details
Overview
1SMC30AT3 from ON Semiconductor is a unidirectional 1500 W transient voltage suppressor (TVS) diode designed for parallel clamping protection of DC power rails and signal lines. It features a 30 V working peak reverse voltage (VRWM), 36.8 V minimum breakdown voltage (VBR), 48.4 V maximum clamping voltage (VC) at 31 A peak pulse current (IPP), and sub-1 ns response time. It is used in automotive power supply inputs, industrial PLC I/O modules, and telecom line cards to absorb ESD and lightning-induced surges.
For engineers reviewing the 1SMC30AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin relative to protected IC VDD, surge current handling under 10/1000 µs waveform, UL 497B certification for isolated loop protection, thermal derating above 75°C, and SMC package solderability per JEDEC J-STD-020.
Technical Context
The 1SMC30AT3 operates as a silicon avalanche diode with sharp Zener-type breakdown characteristics, enabling fast transition from high-impedance blocking state to low-impedance clamping mode during transients. Its unidirectional polarity supports DC-biased applications where reverse conduction must be blocked until breakdown threshold is exceeded.
Thermal design relies on junction-to-lead resistance (RJL = 18.3 °C/W) and junction-to-ambient resistance (RJA = 165 °C/W) under defined PCB footprint conditions. It complies with UL 497B for isolated loop circuit protection and meets Class 3 ESD immunity (>16 kV HBM).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 30 V - Maximum continuous reverse operating voltage before clamping begins; sets minimum system DC rail rating. |
| VBR (min) | 33.3 V @ 1 mA - Guaranteed avalanche onset voltage; defines lower bound of clamping window. |
| VC (max) | 48.4 V @ 31 A - Maximum clamped voltage during 10/1000 µs surge; determines peak stress on downstream ICs. |
| IPP | 31 A - Peak pulse current capability at 1 ms pulse width; correlates to 1500 W peak power dissipation. |
| IR @ VRWM | 5 µA - Reverse leakage at rated working voltage; ensures minimal standby power loss in high-impedance circuits. |
| Response Time | < 1 ns - Time from transient edge to clamping onset; critical for protecting fast logic and analog interfaces. |
| Package | SMC (Case 403) - Surface-mount thermoset plastic package with modified L-bend leads; supports 260°C reflow for 10 s. |
Pinout & Package
1SMC30AT3 uses the SMC (Case 403) surface-mount package: 7.75–8.13 mm length × 6.60–7.11 mm width × 1.90–2.41 mm height, with cathode indicated by molded notch. Leads are modified L-bend for enhanced pad contact area and solder joint reliability.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during forward conduction; connected to ground or low-side reference in unidirectional configuration. | Must be tied to lowest potential node in protected circuit; determines polarity of clamping action. |
| Cathode | Current exit terminal during reverse breakdown; connected to protected line or positive rail. | Carries full surge current during clamping; requires low-inductance trace routing to minimize overshoot. |
Key Features
| Feature | Design Value |
|---|---|
| UL 497B Recognition | Qualified for isolated loop protector classification - enables use in safety-critical telecom and medical isolation barriers without additional certification effort. |
| 1500 W Peak Power Rating | Rated for non-repetitive 10/1000 µs surges up to 31 A - exceeds IEC 61000-4-5 Level 4 (4 kV line-to-line) requirements with margin. |
| Pb-Free (RoHS Compliant) | G-suffix indicates lead-free Surmetic package - compatible with lead-free reflow profiles and global environmental compliance mandates. |
| Low Clamping Ratio | VC / VBR ≈ 1.46 (48.4 V / 33.3 V) - tight voltage window minimizes overvoltage stress on protected ICs while maintaining robust surge margin. |
| ESD Robustness | Class 3 HBM (>16 kV) - protects against human-body model discharges common in manufacturing and field service environments. |
Applications
| Automotive Power Input Protection | Industrial PLC Digital I/O Protection |
|---|---|
Use Scenario: 12 V battery-fed ECUs exposed to load dump (ISO 7637-2 Pulse 5a) and jump-start transients. IC Role / Device Role / Timing Role: Unidirectional TVS placed between power rail and chassis ground to clamp surges above 30 V. Use Value: Limits peak voltage to ≤48.4 V during 31 A transients, preventing damage to 36 V-rated DC-DC controllers and microcontrollers. |
Use Scenario: 24 V digital input modules receiving signals from field sensors in noisy factory environments. IC Role / Device Role / Timing Role: Parallel-connected TVS on each input channel to shunt induced EFT/burst noise (IEC 61000-4-4) and lightning-induced surges. Use Value: Sub-1 ns response ensures clamping occurs before sensitive optocoupler or Schmitt-trigger inputs experience destructive overvoltage. |
| Telecom Line Card Surge Protection | Medical Isolated Power Supply Clamp |
Use Scenario: -48 V DC-powered telecom line cards subject to lightning-induced longitudinal surges on tip/ring pairs. IC Role / Device Role / Timing Role: Paired unidirectional TVS devices across differential lines referenced to isolated ground plane. Use Value: UL 497B recognition validates suitability for primary-side protection in telecom isolators, supporting regulatory approval. |
Use Scenario: Secondary-side 5 V/12 V outputs of medical-grade isolated AC-DC supplies powering patient-connected monitoring circuits. IC Role / Device Role / Timing Role: Final-stage clamping device on low-voltage output rails to prevent fault propagation into patient-connected subsystems. Use Value: Low leakage (<5 µA @ 30 V) avoids loading precision voltage references; tight clamping preserves ADC accuracy during transient events. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ30A | Same VRWM (30 V) and VC (48.4 V), but lower PPK = 600 W (IPP = 12.3 A); SMB package (smaller footprint, higher RJA). | Not suitable for 1500 W surge events; limited to lower-energy transients like ESD or EFT. | Select when space-constrained layouts prioritize footprint over surge energy handling. |
| 1.5SMC30A | Identical electrical specs and SMC package, but obsolete marking (no 'G' suffix); RoHS status not guaranteed; no UL 497B listing. | Lacks UL 497B certification required for telecom/medical isolated loop designs. | Prefer 1SMC30AT3 for new designs requiring safety certification and Pb-free compliance. |
Compared with SMBJ30A and 1.5SMC30A, the 1SMC30AT3 delivers full 1500 W surge capacity in an industry-standard SMC package with documented UL 497B recognition and guaranteed Pb-free construction - making it the only option among the three qualified for high-energy, safety-certified applications.
Availability
1SMC30AT3 is available at Aetrix Electronics and suitable for automotive ECUs, industrial PLC I/O modules, telecom line cards, and medical isolated power supplies requiring stable component supply and long-term lifecycle support.
Supply support for 1SMC30AT3 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 is a global semiconductor manufacturer specializing in power management, analog, sensor, and discrete solutions for automotive, industrial, and communications markets.
The 1SMC30AT3 belongs to the SMC-series transient voltage suppressors - engineered for high-energy surge clamping in harsh environments, with emphasis on reliability, safety certification, and manufacturability in automated SMT assembly.
FAQ
What is the maximum clamping voltage of the 1SMC30AT3 under standard test conditions?
The 1SMC30AT3 has a maximum clamping voltage (VC) of 48.4 V when subjected to its rated peak pulse current (IPP) of 31 A using the 10/1000 µs waveform. This value is measured at TA = 25°C and defines the upper voltage limit imposed on protected circuitry during surge events. The 1SMC30AT3 maintains this clamping performance across its specified operating temperature range, with minor derating above 25°C per the pulse derating curve in the datasheet.
Is the 1SMC30AT3 suitable for bidirectional transient suppression?
No, the 1SMC30AT3 is a unidirectional TVS diode and is not suitable for bidirectional suppression. Its design allows conduction only in reverse breakdown (cathode-to-anode) above VRWM; forward conduction follows standard silicon diode behavior with VF ≤ 3.5 V at 100 A. For AC or bipolar signal line protection, a dedicated bidirectional part such as the 1SMC30AT3's counterpart in a dual-diode configuration would be required - the 1SMC30AT3 itself provides no symmetrical clamping capability.
Does the 1SMC30AT3 meet UL 497B requirements for isolated loop protection?
Yes, the entire 1SMC5.0AT3 series - including the 1SMC30AT3 - carries Underwriters Laboratories recognition under UL 497B for protectors (File #E210057, Classification QVGQ2). This certification covers performance in isolated loop circuits, including passing the Strike Voltage Breakdown, Endurance Conditioning, Dielectric Withstand, and Discharge tests. The 1SMC30AT3 is explicitly listed in ON Semiconductor's UL documentation as compliant, distinguishing it from non-certified alternatives.
What is the thermal resistance from junction to ambient for the 1SMC30AT3?
The 1SMC30AT3 has a junction-to-ambient thermal resistance (RJA) of 165 °C/W when mounted on an FR-4 board using ON Semiconductor's minimum recommended footprint (per Case 403 outline). This value assumes natural convection cooling and is used to calculate junction temperature rise under steady-state power dissipation. For pulsed operation, junction temperature is dominated by transient thermal impedance, and the 1SMC30AT3's 18.3 °C/W junction-to-lead (RJL) becomes more relevant for short-duration surges.
How does the 1SMC30AT3 differ from the older 1.5SMC30A part?
The 1SMC30AT3 replaces the 1.5SMC30A with identical electrical specifications (VRWM = 30 V, VC = 48.4 V, PPK = 1500 W) but adds UL 497B certification, guaranteed Pb-free construction ('G' suffix), and updated Surmetic packaging. The 1.5SMC30A lacks formal safety listing and may contain lead; its marking format and qualification data are outdated. For new designs requiring compliance, reliability, and long-term supply assurance, the 1SMC30AT3 is the direct, certified successor to the 1.5SMC30A.
1SMC30AT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- -
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- -
- Unidirectional Channels:
- -
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- -
- Voltage - Breakdown (Min):
- -
- Voltage - Clamping (Max) @ Ipp:
- -
- Current - Peak Pulse (10/1000µs):
- -
- Power - Peak Pulse:
- -
- Power Line Protection:
- -
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -
- Grade:
- -
- Qualification:
- -
- Mounting Type:
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- Supplier Device Package:
- -
1SMC30AT3 FAQ
1.How can I place an order for 1SMC30AT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMC30AT3 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 1SMC30AT3 reliable?
The price and inventory of 1SMC30AT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMC30AT3 is usually 5 days.
3.What payment methods are accepted for 1SMC30AT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMC30AT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMC30AT3?
1SMC30AT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMC30AT3 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 1SMC30AT3?
For technical support, including 1SMC30AT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMC30AT3 requirements.
6.How does Aetrix verify that 1SMC30AT3 is sourced from the original manufacturer or authorized distributors?
All 1SMC30AT3 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 1SMC30AT3 meets industry standards.
7.What is the process for return or replacement of 1SMC30AT3?
All 1SMC30AT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMC30AT3, 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 1SMC30AT3 part is unused and in its original packaging.
Return procedure for 1SMC30AT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMC30AT3 Tags
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