My Inquiry
My Account
onsemi 1SMB26AT3
- Part No.:
- 1SMB26AT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AA, SMB
- Datasheet:
-
1SMB26AT3.pdf
- Description:
- TVS DIODE 26VWM 42.1VC SMB
- Quantity:
- Payment:
- Shipping:
Inventory:6,820
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1SMB26AT3 from ON Semiconductor is a unidirectional 600 W transient voltage suppressor (TVS) diode designed for parallel overvoltage protection of sensitive electronics. It features a 26 V working peak reverse voltage (VRWM), 31.9 V minimum breakdown voltage (VBR) at 1 mA, 42.1 V maximum clamping voltage (VC) at 14.2 A peak pulse current (IPP), and sub-1 ns response time - deployed in power supply input stages, automotive ECUs, and industrial I/O interfaces.
For engineers reviewing the 1SMB26AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include clamping performance under 1 ms 600 W surges, UL 497B recognition for isolated loop protection, low leakage (<5 µA above 10 V), and SMB package compatibility with high-density SMT layouts.
Technical Context
The 1SMB26AT3 operates as a Zener-based unidirectional TVS, leveraging avalanche breakdown to clamp transients while maintaining low dynamic impedance. Its design targets single-pulse surge events per IEC 61000-4-5 (10/1000 µs waveform), with thermal derating defined up to 150°C junction temperature and validated clamping behavior across −65°C to +150°C operating range.
It delivers 42.1 V clamping at 14.2 A IPP with 630 pF typical junction capacitance at 0 V bias, enabling effective suppression of fast-rising ESD and lightning-induced transients without compromising signal integrity in DC-biased lines. The device meets Class 3 HBM ESD rating (>16 kV) and is UL 497B recognized for isolated loop circuit protection.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power | 600 W @ 1 ms - sustains single high-energy surges without failure |
| Working Peak Reverse Voltage (VRWM) | 26 V - sets maximum continuous DC or peak AC operating voltage before clamping initiates |
| Breakdown Voltage (VBR) | 30.4–31.9 V @ 1 mA - defines onset of avalanche conduction under controlled test conditions |
| Clamping Voltage (VC) | 42.1 V @ 14.2 A IPP - maximum voltage seen by protected circuit during worst-case surge |
| Leakage Current (IR) | <5.0 µA @ 26 V - ensures minimal standby power loss and signal loading in active circuits |
| Response Time | <1.0 ns - enables suppression of nanosecond-scale ESD transients before downstream damage occurs |
| Junction Capacitance | 630 pF @ 0 V - impacts high-frequency noise filtering and signal line bandwidth in AC-coupled paths |
Pinout & Package
1SMB26AT3 is housed in the SMB (Case 403A) surface-mount plastic package: void-free thermosetting body, cathode indicated by polarity band, modified L-bend leads for enhanced pad adhesion, and rated for 260°C soldering (10 s).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Current entry terminal during forward conduction or surge clamping | Connected to system ground or low-side reference in unidirectional protection configuration |
| Cathode | Current exit terminal during reverse-biased clamping | Connected to protected line (e.g., VIN, signal rail); polarity band identifies this terminal |
Key Features
| Feature | Design Value |
|---|---|
| UL 497B Recognition | Validated for isolated loop circuit protection - satisfies safety compliance in telecom and industrial interfaces |
| ESD Robustness | Class 3 HBM (>16 kV) - withstands human-body model discharges without parameter shift or failure |
| Surmetic® Packaging | ON Semiconductor's proprietary transfer-molded plastic - ensures void-free encapsulation and long-term reliability under thermal cycling |
| Low Clamping Ratio | VC/VBR ≈ 1.38 - tight voltage margin between breakdown and clamping improves protection headroom |
| Pb-Free Option | G-suffix variant available - complies with RoHS Directive 2011/65/EU without performance trade-offs |
Applications
| Industrial Power Supply Input Protection | Automotive Body Control Module (BCM) I/O |
|---|---|
|
Use Scenario: Protects 24 V DC input rails in programmable logic controllers (PLCs) against load dump and ISO 7637-2 pulses. IC Role / Device Role / Timing Role: Unidirectional TVS placed between input rail and chassis ground to shunt surge energy before it reaches upstream regulators and microcontrollers. Use Value: Limits transient voltage to ≤42.1 V, preventing latch-up or permanent damage to 36 V-rated input-stage MOSFETs and gate drivers. |
Use Scenario: Shields LIN bus transceivers and sensor inputs in BCMs from battery reversal and jump-start transients. IC Role / Device Role / Timing Role: Parallel-connected TVS on each LIN line (VBAT and LIN) referenced to ground, activated within <1 ns of overvoltage onset. Use Value: Maintains signal integrity by clamping to 42.1 V while adding only 630 pF capacitance - avoids distortion of 19.2 kbps LIN signaling. |
| Medical Equipment Power Entry | Telecom DSL Line Interface |
|
Use Scenario: Safeguards AC/DC adapter outputs in patient-monitoring devices against mains-borne surges per IEC 61000-4-5 Level 3. IC Role / Device Role / Timing Role: Final-stage TVS on regulated 5 V/12 V outputs, positioned immediately before connector pins to minimize trace inductance. Use Value: Delivers 600 W peak power handling with <5 µA leakage - preserves low-noise operation and meets UL 497B isolation requirements. |
Use Scenario: Protects ADSL/VDSL line drivers and receivers from lightning-induced surges on twisted-pair copper lines. IC Role / Device Role / Timing Role: Bidirectional protection not required; unidirectional 1SMB26AT3 used on DC-biased phantom-powered lines where polarity is fixed. Use Value: Achieves 42.1 V clamping with 14.2 A IPP - compatible with GR-1089-CORE surge limits while minimizing capacitive loading on high-frequency data paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ26A | Same VRWM (26 V), identical SMB package, but lower PPK = 600 W and VC = 42.1 V - matches 1SMB26AT3 spec-for-spec per datasheet | No functional difference; validated for same IEC 61000-4-5 and ISO 7637-2 use cases | Select when sourcing from manufacturers offering dual-source availability without layout change |
| 1.5SMC26A | Higher PPK = 1500 W, larger SMC package (7.1 mm × 6.2 mm vs. SMB's 4.6 mm × 3.95 mm), same VRWM/VC specs | Requires PCB footprint revision; suited for higher-energy environments where 600 W margin is insufficient | Choose only if surge threat level exceeds 600 W or thermal dissipation demands larger case size |
Compared with SMBJ26A and 1.5SMC26A, the 1SMB26AT3 offers identical electrical protection performance in the smallest standardized SMB footprint, enabling compact designs without sacrificing UL 497B recognition or HBM ESD robustness - making it optimal for space-constrained industrial and automotive modules.
Availability
1SMB26AT3 is available at Aetrix Electronics and suitable for industrial power supplies, automotive control units, medical equipment power entry, and telecom line interfaces requiring stable component supply and full compliance documentation.
Supply support for 1SMB26AT3 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, and cloud infrastructure markets.
The 1SMB26AT3 belongs to the SMB series of unidirectional TVS diodes engineered for high-reliability transient suppression in harsh environments - targeting applications demanding UL recognition, low clamping ratio, and proven surge survivability.
FAQ
What is the maximum clamping voltage of the 1SMB26AT3 under surge conditions?
The 1SMB26AT3 has a maximum clamping voltage (VC) of 42.1 V when subjected to its rated peak pulse current (IPP) of 14.2 A with a 1 ms pulse width. This value is measured per the standard 10/1000 µs waveform and defines the upper voltage limit imposed on protected circuitry during transient events - critical for ensuring downstream components remain within their absolute maximum ratings. The 1SMB26AT3 maintains this clamping performance across its full operating temperature range.
Does the 1SMB26AT3 meet UL safety standards for circuit protection?
Yes, the 1SMB26AT3 is UL 497B recognized (File #E210057) for isolated loop circuit protection. This certification confirms successful completion of multiple tests including Strike Voltage Breakdown, Endurance Conditioning, Dielectric Withstand, and Discharge testing - distinguishing it from components with only flammability-rated packaging. The 1SMB26AT3's UL recognition supports compliance in telecom, industrial control, and medical equipment where regulatory approval is mandatory.
What is the junction capacitance of the 1SMB26AT3 and how does it affect high-speed signal lines?
The 1SMB26AT3 exhibits 630 pF typical junction capacitance at 0 V bias and 1 MHz. While this value is appropriate for DC power rails and low-to-medium speed interfaces (e.g., LIN, RS-485), it may attenuate or distort signals above ~1 MHz. For high-speed data lines like USB or Ethernet, lower-capacitance TVS devices (e.g., <100 pF) are recommended. The 1SMB26AT3's capacitance is a direct trade-off for its 600 W surge capability and should be evaluated against signal bandwidth requirements in the final design.
Can the 1SMB26AT3 be used in bidirectional protection configurations?
No, the 1SMB26AT3 is a unidirectional TVS diode and must not be used for bidirectional surge suppression. Its internal Zener structure conducts only in reverse bias above VRWM and forward-biases like a standard diode below ~0.7 V - offering no clamping in the negative voltage direction. For AC or bipolar signal lines, dedicated bidirectional variants such as 1SMB26CAT3 must be selected. Using the 1SMB26AT3 in bidirectional roles risks unprotected negative transients damaging downstream circuitry.
What is the thermal resistance and power derating behavior of the 1SMB26AT3?
The 1SMB26AT3 has a thermal resistance from junction-to-ambient (RJA) of 226°C/W on FR-4 board with minimum recommended footprint, and junction-to-lead (RJL) of 40°C/W. Its DC power dissipation derates linearly above 25°C ambient (0.44 mW/°C) and above 75°C lead temperature (25 mW/°C). These values define safe continuous power handling - for example, at 75°C ambient, usable DC power drops to 0.33 W. The 1SMB26AT3 is intended for transient, not steady-state, power dissipation.
1SMB26AT3 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):
- 26V
- Voltage - Breakdown (Min):
- 28.9V
- Voltage - Clamping (Max) @ Ipp:
- 42.1V
- Current - Peak Pulse (10/1000µs):
- 14.2A
- Power - Peak Pulse:
- 600W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 630pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMB
1SMB26AT3 FAQ
1.How can I place an order for 1SMB26AT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMB26AT3 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 1SMB26AT3 reliable?
The price and inventory of 1SMB26AT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMB26AT3 is usually 5 days.
3.What payment methods are accepted for 1SMB26AT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMB26AT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMB26AT3?
1SMB26AT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMB26AT3 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 1SMB26AT3?
For technical support, including 1SMB26AT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMB26AT3 requirements.
6.How does Aetrix verify that 1SMB26AT3 is sourced from the original manufacturer or authorized distributors?
All 1SMB26AT3 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 1SMB26AT3 meets industry standards.
7.What is the process for return or replacement of 1SMB26AT3?
All 1SMB26AT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMB26AT3, 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 1SMB26AT3 part is unused and in its original packaging.
Return procedure for 1SMB26AT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMB26AT3 Tags
-
ESD9B5.0ST5G
onsemi
-
DESD3V3E1BL-7B
Diodes Incorporated
-
ESD5Z3.3T1G
onsemi
-
D5V0H1B2LP-7B
Diodes Incorporated
-
D5V0P1B2LP-7B
Diodes Incorporated
-
DESD5V0U1BA-7
Diodes Incorporated
-
ESD5Z5.0T1G
onsemi
-
DESD5V0U1BB-7
Diodes Incorporated
-
D12V0L1B2LP-7B
Diodes Incorporated
-
PESD2V0Y1BSFYL
Nexperia USA Inc.
-
DF2S5M4CT,L3F
Toshiba Semiconductor and Storage
-
D5V0L1B2WS-7
Diodes Incorporated
Tech Hub
Schmitt triggers use separate rising and falling thresholds to stabilize slow or noisy signals. This guide covers hysteresis, 74HC14 and 74HCT14 selection, comparator calculations, RC oscillators and p…
Counterfeit components can hide behind convincing markings and passing basic function tests. This engineering reference covers source traceability, external inspection, X-ray, XRF, electrical testing, …
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
