My Inquiry
My Account
onsemi 1SMA15AT3
- Part No.:
- 1SMA15AT3
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
1SMA15AT3.pdf
- Description:
- TVS DIODE 15VWM 24.4VC SMA
- Quantity:
- Payment:
- Shipping:
Inventory:6,913
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
1SMA15AT3 from ON Semiconductor is a unidirectional 400 W peak power Zener transient voltage suppressor (TVS) designed for clamping high-energy transients in DC power lines and signal paths. It features a 15 V working peak reverse voltage (VRWM), 16.7–18.5 V breakdown voltage (VBR) at 1 mA test current, 24.4 V clamping voltage (VC) at 16.4 A peak pulse current (IPP), and sub-1 ns response time. It is used in automotive power supply protection and industrial control I/O interfaces.
For engineers reviewing the 1SMA15AT3 datasheet, pinout, applications, or equivalent options, key selection criteria include VRWM margin over operating voltage, clamping ratio (VC/VBR), surge current capability under 10/1000 µs waveform, and SMA package thermal performance on FR-4 PCBs.
Technical Context
The 1SMA15AT3 operates as a unidirectional avalanche diode, conducting only during reverse overvoltage events above its VBR threshold while maintaining low leakage (<2.5 µA at VRWM = 15 V). Its junction design enables fast turn-on with typical response <1 ns and clamps transients to ≤24.4 V at 16.4 A IPP under standardized 10/1000 µs waveform.
Thermal management relies on low thermal resistance (RJA = 250 °C/W, RJL = 20 °C/W) and is validated for 260 °C soldering (10 s). The device is rated for −65 °C to +150 °C operation and meets Class 3 ESD (>16 kV HBM), making it suitable for harsh-environment front-end protection without series impedance.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Power Dissipation | 400 W @ 1 ms, 10/1000 µs waveform - defines maximum single-event surge energy handling |
| Working Peak Reverse Voltage (VRWM) | 15 V - maximum continuous reverse voltage before significant leakage; sets minimum system operating margin |
| Breakdown Voltage (VBR) | 16.7–18.5 V @ 1 mA - precise avalanche onset range used to select clamping headroom |
| Clamping Voltage (VC) | 24.4 V @ 16.4 A IPP - actual voltage seen by protected circuit during worst-case surge |
| Response Time | <1 ns - ensures suppression initiates before sensitive ICs experience overstress |
| ESD Rating | Class 3 (>16 kV HBM) - qualifies for direct interface protection in user-accessible ports |
| Junction-to-Lead Thermal Resistance | 20 °C/W - enables sustained power dissipation when mounted on copper pads per CASE 403D footprint |
Pinout & Package
The 1SMA15AT3 is housed in an SMA (DO-214AC) surface-mount plastic package (CASE 403D-02), featuring a low-profile, flat-handling surface optimized for top-slide or bottom-board mounting. Polarity is marked by a cathode band.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Forward conduction terminal / Reference ground node in unidirectional configuration | Connected to system ground or lower-potential rail; establishes reference for clamping action |
| Cathode | Transient voltage sensing and clamping node | Connected to protected line (e.g., 12 V rail); conducts avalanche current to ground when VRWM exceeded |
Key Features
| Feature | Design Value |
|---|---|
| 400 W peak pulse power rating | Supports robust protection against ISO 7637-2 Pulse 1/2a/5a in 12 V automotive systems |
| Low clamping ratio (VC/VBR ≈ 1.42) | Minimizes overvoltage stress on downstream regulators and microcontrollers |
| Sub-1 ns response time | Prevents EFT/burst transients from propagating past the device into sensitive analog or digital circuitry |
| Pb-free (1SMA15AT3G) and RoHS-compliant option | Enables compliance with environmental regulations without derating or footprint change |
| Flat handling surface & top/bottom mount design | Improves pick-and-place accuracy and supports dual-side PCB assembly |
Applications
| Automotive Power Line Protection | Industrial PLC Digital I/O Protection |
|---|---|
Use Scenario: 12 V battery feed line in engine control unit exposed to load dump (ISO 16750-2) and alternator ripple. IC Role / Device Role / Timing Role: Unidirectional TVS clamp placed between power rail and chassis ground to limit transient excursions. Use Value: Clamps 12 V line to ≤24.4 V during 400 W surges, protecting 3.3 V/5 V LDOs and CAN transceivers without crowbar action. |
Use Scenario: 24 V digital input channel on programmable logic controller receiving signals from field sensors. IC Role / Device Role / Timing Role: Front-end transient suppressor on isolated input stage, shunting induced surges before optocoupler or Schmitt trigger. Use Value: Withstands repeated 1 kV EFT bursts (IEC 61000-4-4) due to low zener impedance and fast response, preserving signal integrity. |
| Medical Equipment Power Supply Input | Point-of-Sale Terminal USB Port ESD Protection |
Use Scenario: AC/DC adapter output feeding isolated DC-DC converters in patient-monitoring devices. IC Role / Device Role / Timing Role: Secondary-side overvoltage clamp on regulated 5 V/12 V outputs to prevent fault propagation. Use Value: Meets IEC 60601-1 creepage/clearance requirements via compact SMA package and achieves >16 kV HBM ESD immunity. |
Use Scenario: VBUS line of USB 2.0 port in retail kiosk exposed to frequent human contact. IC Role / Device Role / Timing Role: Primary ESD suppressor placed directly at connector, referenced to system ground. Use Value: Limits ESD-induced voltage to <24.4 V within <1 ns, preventing latch-up in USB transceiver ICs per IEC 61000-4-2 Level 4. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ15A (Bourns) | Same VRWM (15 V), higher IPP (21.2 A), larger SMB package (higher thermal mass) | Better suited for higher average surge duty cycles due to 600 W peak rating and lower RJA | Select when board space allows SMB and long-term reliability under repetitive surges is critical |
| P6SMB15A (Littelfuse) | Identical electrical specs (VRWM = 15 V, VC = 24.4 V @ 16.4 A), same SMA package, AEC-Q200 qualified | Validated for automotive-grade temperature cycling and vibration; preferred for OEM production | Choose for automotive Tier-1 designs requiring AEC-Q200 documentation and PPAP support |
Compared with SMBJ15A and P6SMB15A, the 1SMA15AT3 offers identical clamping performance in a cost-optimized SMA footprint but lacks AEC-Q200 certification and has lower peak power margin; P6SMB15A adds qualification rigor while SMBJ15A trades size for enhanced thermal endurance.
Availability
1SMA15AT3 is available at Aetrix Electronics and suitable for automotive power line protection, industrial PLC I/O hardening, and medical equipment power supply inputs requiring stable component supply across extended production lifecycles.
Supply support for 1SMA15AT3 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 power management, analog, sensor, and connectivity solutions for automotive, industrial, and cloud power applications.
The 1SMA15AT3 belongs to the SMA-series transient voltage suppressors, engineered for cost-sensitive, high-reliability overvoltage protection in DC power rails and signal lines where fast response and predictable clamping are essential.
FAQ
What is the maximum clamping voltage of the 1SMA15AT3 under standard surge conditions?
The 1SMA15AT3 exhibits a maximum clamping voltage (VC) of 24.4 V when subjected to its rated peak pulse current (IPP) of 16.4 A under the standardized 10/1000 µs waveform. This value is measured at TA = 25°C and represents the upper bound voltage imposed on the protected circuit during worst-case transient events. Designers use this parameter to verify that downstream components remain within their absolute maximum ratings.
Does the 1SMA15AT3 have a bidirectional variant?
No, the 1SMA15AT3 is strictly unidirectional. Bidirectional variants in the same SMA family carry different part number suffixes and markings - for example, the 1SMA15CAT3 is the bidirectional counterpart. The 1SMA15AT3's cathode band indicates polarity, and it conducts only during reverse overvoltage; forward conduction follows standard silicon diode behavior with VF ≤ 3.5 V at 30 A.
What is the thermal resistance from junction to ambient for the 1SMA15AT3?
The 1SMA15AT3 has a thermal resistance from junction to ambient (RJA) of 250 °C/W when mounted on an FR-4 PCB using ON Semiconductor's minimum recommended footprint (per CASE 403D outline). This value assumes no additional copper pour; adding thermal vias or copper planes reduces effective RJA and improves surge survivability during repetitive events.
Can the 1SMA15AT3 be used in place of a Zener diode for voltage regulation?
The 1SMA15AT3 is not intended for steady-state voltage regulation. While it exhibits Zener-like breakdown behavior, its parameters (e.g., VBR tolerance ±5%, high dynamic impedance above IT) are optimized for transient suppression-not precision regulation. For regulation, dedicated Zener diodes with tighter tolerance, lower zener impedance, and specified regulation current should be used instead of the 1SMA15AT3.
What does the "T3" suffix indicate in the 1SMA15AT3 part number?
The "T3" suffix in 1SMA15AT3 denotes tape-and-reel packaging: 5000 units per reel, compatible with automated SMT placement equipment. It specifies the shipping format and does not affect electrical or thermal characteristics. The "G" suffix (e.g., 1SMA15AT3G) indicates Pb-free construction, while "T3" remains consistent across both leaded and RoHS-compliant versions.
1SMA15AT3 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- DO-214AC, SMA
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 15V
- Voltage - Breakdown (Min):
- 16.7V
- Voltage - Clamping (Max) @ Ipp:
- 24.4V
- Current - Peak Pulse (10/1000µs):
- 16.4A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- 758pF @ 1MHz
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SMA
1SMA15AT3 FAQ
1.How can I place an order for 1SMA15AT3 through Aetrix?
Please submit a Request for Quotation (RFQ) for 1SMA15AT3 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 1SMA15AT3 reliable?
The price and inventory of 1SMA15AT3 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for 1SMA15AT3 is usually 5 days.
3.What payment methods are accepted for 1SMA15AT3?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for 1SMA15AT3 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for 1SMA15AT3?
1SMA15AT3 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your 1SMA15AT3 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 1SMA15AT3?
For technical support, including 1SMA15AT3 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your 1SMA15AT3 requirements.
6.How does Aetrix verify that 1SMA15AT3 is sourced from the original manufacturer or authorized distributors?
All 1SMA15AT3 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 1SMA15AT3 meets industry standards.
7.What is the process for return or replacement of 1SMA15AT3?
All 1SMA15AT3 units undergo pre-shipment inspection (PSI). If there is an issue with 1SMA15AT3, 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 1SMA15AT3 part is unused and in its original packaging.
Return procedure for 1SMA15AT3:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
1SMA15AT3 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
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…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
