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onsemi 1SMB48AT3
- Part No.:
- 1SMB48AT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
1SMB48AT3.pdf
- Description:
- TVS DIODE 48VWM 77.4VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:5,910
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Product details
Overview
1SMB48AT3 from ON Semiconductor is a unidirectional 600 W peak power Zener transient voltage suppressor (TVS) in SMB package, designed for parallel overvoltage protection of sensitive electronics. It features a 48 V working peak reverse voltage (VRWM), 58.9 V minimum breakdown voltage (VBR) at 1 mA, and clamps to ≤77.4 V at 7.7 A peak pulse current (IPP), making it suitable for DC power rail protection in industrial power supplies and automotive ECUs.
For engineers reviewing the 1SMB48AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping voltage margin vs. system operating voltage, surge current capability under 1 ms 10/1000 µs waveform, UL 497B recognition for isolated loop protection, and Pb-free SMB package compatibility with automated SMT assembly.
Technical Context
The 1SMB48AT3 operates as a voltage-clamping device in reverse-biased configuration, triggering when transient voltage exceeds its VBR and limiting downstream voltage to VC during high-energy surges. Its low zener impedance and <1.0 ns response time enable fast suppression of ESD and lightning-induced transients.
It is rated for 600 W non-repetitive peak power at TL = 25°C with 1 ms pulse width, derates linearly above 75°C junction temperature, and maintains <5.0 µA leakage at VRWM. The device meets Class 3 (>16 kV) HBM ESD rating and UL 497B certification for isolated loop circuit protection.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 48 V - Maximum continuous reverse operating voltage before clamping begins; must be ≥ system DC bus voltage. |
| VBR (min) | 58.9 V @ 1 mA - Guaranteed minimum breakdown threshold; ensures reliable turn-on above normal operating range. |
| VC @ IPP | 77.4 V @ 7.7 A - Clamped voltage during 1 ms 10/1000 µs surge; defines maximum stress on protected ICs. |
| PPK | 600 W - Peak transient energy absorption capacity; validates suitability for IEC 61000-4-5 Level 3/4 surges. |
| IR @ VRWM | 5.0 µA - Reverse leakage at rated working voltage; negligible power loss in standby operation. |
| Response Time | <1.0 ns - Enables suppression of fast-rising ESD events before downstream components experience overstress. |
| UL Recognition | UL 497B QVGQ2 - Certified for use in isolated telecom/data line protectors; supports safety-compliant system design. |
Pinout & Package
1SMB48AT3 uses the SMB (Case 403A) surface-mount plastic package with modified L-bend leads. Cathode is marked by a polarity band; anode is unmarked. Mounting position is unrestricted.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or lowest potential node in clamping configuration; forms return path for surge current. |
| Cathode | High-side transient input terminal | Connected to protected line (e.g., 48 V rail); voltage rise above VBR triggers avalanche conduction to anode. |
Key Features
| Feature | Design Value |
|---|---|
| 600 W peak pulse power | Supports robust protection against IEC 61000-4-5 combination wave surges up to 4 A (line-to-ground) without failure. |
| UL 497B recognition | Validates compliance for telecom/data line isolation barriers, eliminating need for additional safety certification effort. |
| ESD rating >16 kV HBM | Withstands direct human-body model ESD events common in handling and field deployment without parametric shift. |
| Pb-free SMB package | Meets RoHS Directive 2011/65/EU and JEDEC J-STD-020 reflow profile; compatible with lead-free soldering at 260°C/10 s. |
| Low clamping ratio (VC/VBR ≈ 1.31) | Minimizes overvoltage margin between breakdown and clamp, enabling tighter protection windows for 48 V systems. |
Applications
| Industrial Power Supply Protection | Automotive Body Control Module (BCM) |
|---|---|
|
Use Scenario: Protecting 48 V auxiliary power rails in programmable logic controller (PLC) power modules from load dump and inductive switching transients. IC Role / Device Role / Timing Role: Unidirectional TVS diode placed in parallel with DC-DC converter input, clamping surges within 1 ns to prevent MOSFET gate oxide damage. Use Value: Limits transient voltage to ≤77.4 V, maintaining safe margin below 100 V MOSFET VDS rating while absorbing 600 W peak energy. |
Use Scenario: Safeguarding LIN bus transceivers and microcontroller I/O pins in BCMs against battery reverse connection and alternator load dump. IC Role / Device Role / Timing Role: Standoff protection device on 12 V/48 V supply lines, activated only during overvoltage events exceeding 48 V VRWM. Use Value: Provides certified UL 497B isolation barrier compliance and withstands >16 kV ESD per HBM-critical for automotive qualification. |
| Telecom Remote Radio Unit (RRU) | Medical Imaging Power Interface |
|
Use Scenario: Shielding 48 V DC power inputs of outdoor RRU equipment from lightning-induced surges on tower-mounted power feeds. IC Role / Device Role / Timing Role: Primary surge suppression stage upstream of DC-DC converters, conducting full 7.7 A IPP to ground during 10/1000 µs transients. Use Value: Delivers 600 W peak power dissipation with <1 ns response, reducing downstream filter component count and board space. |
Use Scenario: Protecting high-precision analog front-end power rails in MRI gradient amplifier modules from switching noise and ESD coupling. IC Role / Device Role / Timing Role: Low-leakage (5 µA @ 48 V) clamping diode ensuring no signal integrity degradation during normal operation. Use Value: Maintains <5 µA reverse leakage to avoid offset drift in µV-level sensor circuits while providing fail-safe surge shutdown. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ48A | Same VRWM (48 V), but lower PPK (600 W same), higher VC (80.0 V @ 7.5 A), larger SMBJ package (Case 403AC). | Higher clamping voltage reduces protection margin for 48 V systems near 75 V absolute max ratings. | Select 1SMB48AT3 when tighter VC/VBR ratio and smaller SMB footprint are required for dense PCB layouts. |
| SMCJ48A | Same VRWM (48 V), higher PPK (1500 W), higher VC (79.4 V @ 18.9 A), larger SMC package (Case 403D). | Over-specified power rating increases cost and board area; not needed for standard 600 W surge requirements. | Choose 1SMB48AT3 for cost-sensitive, space-constrained 48 V protection where 600 W is sufficient and SMB fit is mandatory. |
Compared with SMBJ48A and SMCJ48A, the 1SMB48AT3 offers optimal balance of clamping performance (77.4 V), compact SMB footprint, and UL 497B certification-making it preferred for 48 V industrial and automotive power interfaces where layout density and safety compliance are critical.
Availability
1SMB48AT3 is available at Aetrix Electronics and suitable for industrial power supplies, automotive body control modules, telecom remote radio units, and medical imaging power interfaces requiring stable component supply and long-term lifecycle support.
Supply support for 1SMB48AT3 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 1SMB48AT3 belongs to the SMB series of unidirectional TVS diodes, engineered specifically for high-reliability transient suppression in harsh environments-including automotive, industrial controls, and telecom infrastructure-where UL recognition and surge robustness are mandatory.
FAQ
What is the clamping voltage of the 1SMB48AT3 at its rated peak pulse current?
The 1SMB48AT3 clamps to a maximum of 77.4 V at its rated peak pulse current (IPP) of 7.7 A under the standard 1 ms 10/1000 µs waveform. This value is measured per Figure 2 in the datasheet and defines the upper voltage limit imposed on protected circuitry during surge events. The 1SMB48AT3 maintains this clamping performance across its specified operating temperature range and is validated for non-repetitive surge conditions.
Is the 1SMB48AT3 RoHS-compliant and lead-free?
Yes, the "G" suffix in 1SMB48AT3G explicitly denotes a Pb-free package compliant with RoHS Directive 2011/65/EU. The 1SMB48AT3 is qualified for lead-free reflow soldering at 260°C for 10 seconds, and its Surmetic molding compound meets JEDEC J-STD-020 moisture sensitivity level (MSL) requirements. All external surfaces are corrosion-resistant and readily solderable.
Does the 1SMB48AT3 have UL recognition, and for what standard?
Yes, the 1SMB48AT3 carries UL 497B recognition under file #E210057, specifically for isolated loop circuit protection (category QVGQ2). This certification covers performance validation across multiple tests including strike voltage breakdown, endurance conditioning, dielectric withstand, and discharge testing-confirming suitability for safety-critical telecom and industrial isolation barriers.
What is the maximum reverse leakage current of the 1SMB48AT3 at its working voltage?
The 1SMB48AT3 exhibits a maximum reverse leakage current (IR) of 5.0 µA when biased at its working peak reverse voltage (VRWM) of 48 V and ambient temperature of 25°C. This low leakage ensures minimal standby power loss and avoids interference with precision analog circuits or high-impedance monitoring nodes downstream of the protected rail.
How does the thermal derating of the 1SMB48AT3 work above 75°C?
The 1SMB48AT3's DC power dissipation (PD) is rated at 3.0 W at TL = 75°C and derates linearly at 25 mW/°C above that temperature. For example, at 100°C lead temperature, PD drops to 2.375 W. This derating applies to continuous power handling-not peak surge capability-and is based on FR-4 board mounting with 1 in² copper pad per datasheet Note 2.
1SMB48AT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AA, SMB
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 48V
- Voltage - Breakdown (Min):
- 53.3V
- Voltage - Clamping (Max) @ Ipp:
- 77.4V
- Current - Peak Pulse (10/1000µs):
- 7.7A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 365pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMB
1SMB48AT3 FAQ
1.How can I place an order for 1SMB48AT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMB48AT3 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 1SMB48AT3 reliable?
The price and inventory of 1SMB48AT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMB48AT3 is usually 5 days.
3.What payment methods are accepted for 1SMB48AT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMB48AT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMB48AT3?
1SMB48AT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMB48AT3 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 1SMB48AT3?
For technical support, including 1SMB48AT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMB48AT3 requirements.
6.How does Aetrix verify that 1SMB48AT3 is sourced from the original manufacturer or authorized distributors?
All 1SMB48AT3 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 1SMB48AT3 meets industry standards.
7.What is the process for return or replacement of 1SMB48AT3?
All 1SMB48AT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMB48AT3, 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 1SMB48AT3 part is unused and in its original packaging.
Return procedure for 1SMB48AT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMB48AT3 Tags
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