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onsemi SMBJ12AONT3G
- Part No.:
- SMBJ12AONT3G
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
SMBJ12AONT3G.pdf
- Description:
- TVS DIODE 12VWM 19.9VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:5,096
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Product details
Overview
SMBJ12AONT3G from onsemi is a unidirectional 600 W peak power transient voltage suppressor (TVS) diode designed for parallel protection of voltage-sensitive circuits against ESD, lightning-induced surges, and inductive switching transients. It features a 12 V working peak reverse voltage (VRWM), 19.9 V clamping voltage at 30.2 A peak pulse current, <1 ns response time, and UL 497B recognition for isolated loop circuit protection - widely deployed in automotive power supplies and industrial communication interfaces.
For engineers reviewing the SMBJ12AONT3G datasheet, pinout, applications, or equivalent options, key selection criteria include clamping performance under 10/1000 µs surge, low leakage (<5 µA @ 12 V), ESD robustness (IEC 61000-4-2 Level 4), thermal derating above 25°C, and Pb-free SMB package compatibility with automated SMT assembly.
Technical Context
The SMBJ12AONT3G operates as a Zener-based unidirectional TVS, triggering when reverse voltage exceeds its 13.2–14.3 V breakdown range (VBR @ IT = 1 mA). Its low zener impedance and fast turn-on enable sub-1 ns response to transients, minimizing overshoot in high-speed protection paths.
It delivers 600 W peak power dissipation (10/1000 µs waveform) at TL = 25°C, with thermal derating to 0.55 W at TA = 25°C and junction-to-ambient thermal resistance of 226°C/W on FR-4 board using ON Semiconductor's recommended footprint. UL 497B recognition confirms compliance for isolated loop surge protection in safety-critical systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Working Peak Reverse Voltage (VRWM) | 12 V - Maximum continuous reverse operating voltage before clamping begins; defines system steady-state voltage margin. |
| Clamping Voltage (VCM) | 19.9 V @ IPP = 30.2 A - Peak voltage seen by protected circuit during worst-case 10/1000 µs surge; determines downstream component stress. |
| Breakdown Voltage (VBR) | 13.2–14.3 V @ IT = 1 mA - Tight tolerance ensures predictable turn-on threshold across production lots. |
| Peak Pulse Power (PPK) | 600 W @ 1 ms - Sustains high-energy transients without failure; validated per IEC 61000-4-5 waveform. |
| ESD Rating | Class 3 (>16 kV HBM, IEC 61000-4-2 Level 4) - Meets stringent electrostatic discharge immunity for automotive and medical equipment. |
| Leakage Current (IR) | <5 µA @ 12 V - Negligible standby power loss and signal integrity impact in always-on interfaces. |
| Response Time | <1 ns - Limits voltage overshoot during fast-rising transients (e.g., relay bounce, EFT bursts). |
Pinout & Package
Package: SMB (Case 403A), surface-mount, Pb-free, cathode-indicated by polarity band. Dimensions: 3.56 mm × 4.32 mm × 1.02 mm (L × W × H); optimized for reflow soldering at 260°C for 10 s.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Low-side reference | Connected to ground or low-impedance return path; forms current sink during clamping. |
| Cathode | Reverse-biased clamping terminal | Connected to protected line (e.g., CAN_H, USB_VBUS); conducts surge current to ground when VRWM exceeded. |
Key Features
| Feature | Design Value |
|---|---|
| UL 497B Recognition (QVGV2) | Validated for isolated loop circuit protection - enables use in telecom and industrial safety-rated designs without additional certification effort. |
| Low Clamping Ratio (VCM/VRWM ≈ 1.66) | Minimizes overvoltage stress on downstream ICs (e.g., RS-485 transceivers, microcontroller I/O) during surge events. |
| Pb-Free & RoHS Compliant | Meets global environmental regulations and supports lead-free reflow profiles (JEDEC J-STD-020). |
| Thermal Derating Curve Provided | Enables accurate power handling estimation across ambient temperatures (−65°C to +150°C operating range). |
| Modified L-Bend Leads | Increases solder joint area and mechanical reliability on PCBs subjected to thermal cycling or vibration. |
Applications
| Automotive Power Supply Protection | Industrial RS-485 Interface |
|---|---|
Use Scenario: Protecting 12 V battery-fed ECUs from load dump and alternator ripple transients. IC Role / Device Role / Timing Role: Unidirectional TVS placed between power rail and chassis ground to clamp surges up to ±60 V. Use Value: Withstands 600 W peak pulses and maintains <5 µA leakage, preserving low-quiescent-current design goals. |
Use Scenario: Safeguarding RS-485 transceiver pins (A/B) against ESD and cable-induced surges in factory automation networks. IC Role / Device Role / Timing Role: Parallel-connected TVS on differential bus lines to limit common-mode overvoltage without distorting signal integrity. Use Value: 19.9 V clamping ensures transceiver remains within absolute maximum ratings even during 4 kV contact ESD events. |
| Medical Equipment Input Stage | Consumer Power Adapter Output |
Use Scenario: Shielding patient-connected monitoring device inputs from ESD and defibrillator-induced transients. IC Role / Device Role / Timing Role: First-line transient suppressor on analog front-end supply rails, certified to UL 497B for isolation barrier compliance. Use Value: UL recognition eliminates need for separate isolation validation; <1 ns response prevents transient coupling into sensitive ADC paths. |
Use Scenario: Suppressing output overvoltage spikes in AC/DC adapters caused by transformer leakage inductance or MOSFET switching. IC Role / Device Role / Timing Role: Clamp diode across secondary-side DC output to protect downstream regulators and USB-PD controllers. Use Value: 12 V VRWM aligns with 5 V/9 V/12 V adapter outputs; low zener impedance ensures stable clamping under dynamic load steps. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ12AT3G (onsemi) | Same electrical specs and package; differs only in marking (no "ON" suffix) and tape/reel packaging variant. | No functional difference; identical in circuit performance and layout. | Select SMBJ12AT3G if standard onsemi part numbering without legacy "ON" branding is preferred. |
| SMCJ12A (Littelfuse) | Higher 1500 W peak power rating, larger SMC package (7.11 mm × 6.22 mm), 22.5 V clamping at 43.3 A. | Better suited for higher-energy surges but requires PCB redesign due to larger footprint and thermal mass. | Choose SMCJ12A only when 600 W is insufficient and board space allows SMC package integration. |
Compared with SMBJ12AT3G, the SMBJ12AONT3G offers identical protection performance with legacy ON Semiconductor marking; versus SMCJ12A, it trades peak energy handling for compact SMB footprint and lower thermal inertia - critical for space-constrained consumer and automotive modules.
Availability
SMBJ12AONT3G is available at Aetrix Electronics and suitable for automotive power supply protection, industrial RS-485 interface hardening, and medical equipment input-stage surge suppression requiring stable component supply and long-term lifecycle support.
Supply support for SMBJ12AONT3G 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power management, analog, sensors, and connectivity solutions for automotive, industrial, cloud, and medical markets.
The SMBJ series was developed specifically for robust, surface-mount transient suppression in harsh environments - emphasizing low clamping ratio, fast response, and regulatory compliance (UL 497B, IEC 61000-4-2) for safety-critical electronics.
FAQ
What is the clamping voltage of SMBJ12AONT3G at its rated peak pulse current?
The SMBJ12AONT3G has a maximum clamping voltage (VCM) of 19.9 V when subjected to a 10/1000 µs surge waveform with a peak pulse current (IPP) of 30.2 A. This value is measured per Figure 1 in the official datasheet and represents the upper voltage limit imposed on protected circuitry during worst-case transient events. The SMBJ12AONT3G maintains this clamping performance across its full operating temperature range.
Is SMBJ12AONT3G compatible with lead-free reflow soldering processes?
Yes, SMBJ12AONT3G is Pb-free and qualified for lead-free reflow soldering per JEDEC J-STD-020. Its package withstands peak temperatures up to 260°C for 10 seconds, matching standard SAC305 profile requirements. The modified L-bend leads enhance wetting and joint reliability during automated assembly - confirmed in onsemi's Soldering and Mounting Techniques Reference Manual (SOLDERRM/D).
Does SMBJ12AONT3G meet IEC 61000-4-2 ESD immunity standards?
Yes, SMBJ12AONT3G is rated to IEC 61000-4-2 Level 4 (±8 kV contact, ±15 kV air), exceeding Class 3 HBM (>16 kV) requirements. This certification is explicitly stated in the datasheet's Specification Features section and verified through onsemi's internal qualification testing - making SMBJ12AONT3G suitable for end-equipment requiring CE marking and industrial ESD resilience.
How does the thermal derating of SMBJ12AONT3G affect its power handling at elevated ambient temperatures?
SMBJ12AONT3G's DC power dissipation derates linearly above 25°C at 4.4 mW/°C, dropping from 0.55 W at 25°C to zero at ~150°C. For pulsed operation, the peak power derating curve (Figure 2) shows ~60% capability retained at 75°C ambient. These curves are essential for designing reliable protection in enclosed enclosures or under-hood automotive locations where SMBJ12AONT3G must sustain repeated surges without thermal runaway.
What is the significance of UL 497B recognition for SMBJ12AONT3G?
UL 497B recognition certifies SMBJ12AONT3G for use in isolated loop circuit protection - covering dielectric withstand, endurance conditioning, and strike voltage breakdown tests. Unlike basic flammability-only certifications, UL 497B validates the device's role in safety-isolated systems (e.g., 4–20 mA loops, PoE interfaces), allowing SMBJ12AONT3G to be directly referenced in safety documentation without additional component-level testing.
SMBJ12AONT3G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AA, SMB
- Series:
- SMBJ
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 12V
- Voltage - Breakdown (Min):
- 13.2V
- Voltage - Clamping (Max) @ Ipp:
- 19.9V
- Current - Peak Pulse (10/1000µs):
- 30.2A (8/20µs)
- Power - Peak Pulse:
- 600W
- 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:
- SMB
SMBJ12AONT3G FAQ
1.How can I place an order for SMBJ12AONT3G through Aetrix?
Please submit a Request for Quotation (RFQ) for SMBJ12AONT3G 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 SMBJ12AONT3G reliable?
The price and inventory of SMBJ12AONT3G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMBJ12AONT3G is usually 5 days.
3.What payment methods are accepted for SMBJ12AONT3G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMBJ12AONT3G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMBJ12AONT3G?
SMBJ12AONT3G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMBJ12AONT3G 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 SMBJ12AONT3G?
For technical support, including SMBJ12AONT3G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMBJ12AONT3G requirements.
6.How does Aetrix verify that SMBJ12AONT3G is sourced from the original manufacturer or authorized distributors?
All SMBJ12AONT3G 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 SMBJ12AONT3G meets industry standards.
7.What is the process for return or replacement of SMBJ12AONT3G?
All SMBJ12AONT3G units undergo pre-shipment inspection (PSI). If there is an issue with SMBJ12AONT3G, 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 SMBJ12AONT3G part is unused and in its original packaging.
Return procedure for SMBJ12AONT3G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMBJ12AONT3G Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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onsemi
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D5V0H1B2LP-7B
Diodes Incorporated
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D5V0P1B2LP-7B
Diodes Incorporated
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DESD5V0U1BA-7
Diodes Incorporated
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ESD5Z5.0T1G
onsemi
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DESD5V0U1BB-7
Diodes Incorporated
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D12V0L1B2LP-7B
Diodes Incorporated
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PESD2V0Y1BSFYL
Nexperia USA Inc.
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DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
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D5V0L1B2WS-7
Diodes Incorporated
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