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onsemi SMF170AT1G
- Part No.:
- SMF170AT1G
- Manufacturer:
- onsemi
- Category:
- TVS Diodes
- Package:
- SOD-123F
- Datasheet:
-
SMF170AT1G.pdf
- Description:
- TVS DIODE 170VWM 275VC SOD123FL
- Quantity:
- Payment:
- Shipping:
Inventory:5,662
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Product details
Overview
SMF170AT1G from onsemi is a unidirectional Zener transient voltage suppressor (TVS) in SOD−123FL package, designed for overvoltage protection of DC power rails and signal lines. It features 170 V working peak reverse voltage (VRWM), 275 A maximum peak pulse current (IPP), 209 V maximum clamping voltage (VC) at IPP, <1 ns response time, and 175 W peak pulse power rating at 10/1000 µs waveform - suitable for protecting industrial power supplies and telecom interface circuits against ESD and lightning-induced surges.
For engineers reviewing the SMF170AT1G datasheet, pinout, applications, or equivalent options, key selection criteria include VRWM ≥ system operating voltage, VC margin relative to protected IC absolute maximum ratings, thermal derating under repeated surge conditions, and IEC61000−4−2/−4 compliance for end-equipment certification.
Technical Context
This TVS diode operates as a voltage-clamped shunt protector: under normal bias it presents high impedance (<1 µA leakage at VRWM), but avalanches rapidly when transient voltage exceeds VBR (189–209 V), diverting surge current away from downstream components. Its low zener impedance ensures stable clamping across wide current range.
Designed for surface-mount integration in space-constrained systems, SMF170AT1G uses thermally optimized SOD−123FL packaging with 26 °C/W junction-to-cathode thermal resistance and MSL 1 reflow compatibility up to 260°C. It meets IEC61000−4−2 Level 4 (±16 kV contact/±25 kV air) and IEC61000−4−4 (40 A, 5/50 ns) immunity standards without external circuitry.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VRWM | 170 V - minimum DC or peak AC voltage the device blocks continuously without conduction |
| VBR (min/max) | 189 V / 209 V - breakdown occurs within this band at 1 mA test current; defines turn-on threshold |
| VC @ IPP | 209 V max at 275 A - maximum voltage seen by protected circuit during worst-case 10/1000 µs surge |
| IPP | 275 A - peak surge current the device safely clamps without failure per IEC61000−4−5 waveform |
| Ppk (10/1000 µs) | 175 W - peak pulse power handling capability; determines survivability of fast, high-energy transients |
| Response Time | <1 ns - enables protection of high-speed interfaces before transient propagates into IC pins |
| ESD Rating | >16 kV HBM - qualifies for Class 3 ESD robustness in handheld and portable equipment |
Pinout & Package
SOD−123FL surface-mount package: 2.5–2.9 mm length × 1.5–1.8 mm width × ≤1.0 mm height; cathode indicated by polarity band; lead finish = 100% matte tin; qualified for 260°C reflow (MSL 1).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (Banded End) | Cathode | Connected to system ground or low-impedance return path; carries full surge current during clamping |
| 2 (Non-banded End) | Anode | Connected to protected line (e.g., VBUS, RS-485 A/B); reverse-biased during normal operation |
Key Features
| Feature | Design Value |
|---|---|
| Low-profile SOD−123FL | Max height 1.0 mm - enables placement beneath connectors or in ultra-thin consumer enclosures |
| Small footprint area | 8.45 mm² - reduces PCB real estate vs. SMA/SMB packages while maintaining thermal performance |
| IEC61000−4−2 Level 4 | ±16 kV contact discharge - eliminates need for secondary ESD protection in USB, HDMI, and Ethernet ports |
| Fast response <1 ns | Clamps before most microcontroller I/O structures experience damage - critical for MCU reset lines and sensor inputs |
| Tape-and-reel packaging | 3,000 units/reel - supports automated SMT assembly without manual handling or static exposure |
Applications
| Industrial Power Supply Input Protection | Telecom Line Interface Protection |
|---|---|
|
Use Scenario: 24–48 V DC input stage of programmable logic controllers (PLCs) exposed to load dump and inductive switching transients. IC Role / Device Role / Timing Role: Shunt clamping element placed between VIN and GND, activated only during overvoltage events >170 V. Use Value: Limits voltage excursion to ≤209 V during 275 A surges, preventing damage to upstream DC/DC converters and downstream FPGA power domains. |
Use Scenario: RS-485 transceiver bus lines (A/B) in building automation networks subject to cable-induced lightning surges. IC Role / Device Role / Timing Role: Unidirectional TVS connected anode-to-line, cathode-to-ground to clamp negative transients on differential pair. Use Value: Maintains signal integrity by clamping common-mode surges within 1 ns, preserving data rates up to 10 Mbps without bit errors. |
| Automotive Body Control Module (BCM) Inputs | Point-of-Load (POL) Converter Output Protection |
|
Use Scenario: Wake-up input lines (e.g., LIN bus, door switch sense) in BCMs subjected to ISO 7637-2 pulse 1/2a/3a transients. IC Role / Device Role / Timing Role: Low-leakage (≤1 µA at 170 V) protector on always-active sensing nodes to avoid battery drain. Use Value: Survives repetitive 100 V/50 A pulses without parameter shift, ensuring 15-year vehicle lifetime reliability. |
Use Scenario: 3.3 V or 5 V output rail of POL converters feeding ASICs/FPGAs in network switches. IC Role / Device Role / Timing Role: Secondary overvoltage guard after primary feedback loop, triggered only if regulation fails catastrophically. Use Value: Clamps output to ≤209 V before downstream logic ICs exceed absolute maximum ratings (typically 6–7 V), preventing latch-up. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ170A | Same VRWM (170 V) and VC (209 V), but SMA package (higher RθJA = 40°C/W vs. 26°C/W); 400 W Ppk rating | Larger footprint (5.2 × 2.7 mm vs. 2.7 × 1.7 mm); better for high-repetition surges but incompatible with dense layouts | Select SMAJ170A only if thermal budget allows larger pad area and board space permits SMA footprint |
| 1.5SMC170A | Higher Ppk (1500 W), DO-214AB package; VRWM = 170 V, VC = 275 V (vs. 209 V for SMF170AT1G) | Clamping voltage 66 V higher - may exceed protected IC's absolute max rating; requires careful margin analysis | Choose 1.5SMC170A only when surge energy exceeds 175 W capability and system can tolerate higher clamping voltage |
Compared with SMAJ170A and 1.5SMC170A, SMF170AT1G offers the smallest PCB footprint and lowest clamping voltage among 170 V TVS diodes, making it optimal for space-constrained, low-voltage-tolerance applications where thermal management is handled via board-level copper pours rather than package size.
Availability
SMF170AT1G is available at Aetrix Electronics and suitable for industrial power supplies, telecom line interfaces, automotive body control modules, and point-of-load converter outputs requiring stable component supply and certified surge immunity.
Supply support for SMF170AT1G 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 IoT markets.
The SMF series is part of onsemi's transient voltage suppression portfolio, engineered specifically for compact, high-reliability DC rail protection in consumer, industrial, and automotive electronics where board space and clamping precision are critical.
FAQ
What is the working peak reverse voltage (VRWM) specification for SMF170AT1G?
The SMF170AT1G has a VRWM of 170 V, meaning it reliably blocks voltages up to this level under continuous DC or peak AC conditions without significant leakage. This value is selected to match or slightly exceed the maximum steady-state voltage of the protected circuit - for example, a 150 V nominal industrial bus - ensuring no false triggering during normal operation while providing headroom for ripple and tolerance.
How does the clamping voltage (VC) of SMF170AT1G compare to its breakdown voltage (VBR)?
SMF170AT1G has a VBR range of 189–209 V at 1 mA and a maximum VC of 209 V at 275 A IPP. Unlike many TVS diodes where VC significantly exceeds VBR, SMF170AT1G exhibits tight clamping - VC equals the upper limit of VBR - indicating minimal voltage overshoot during high-current surges, which is essential for protecting sensitive 200 V-rated capacitors or MOSFETs downstream.
Can SMF170AT1G be used in bidirectional configurations?
No - SMF170AT1G is a unidirectional TVS diode, intended only for DC or single-polarity signal line protection. Its electrical characteristics (e.g., forward voltage VF = 1.25 V at 200 mA) and marking (cathode band) confirm asymmetrical behavior. For AC or differential line protection requiring symmetrical clamping, a dedicated bidirectional part like SMBJ170CA must be used instead of attempting series/parallel combinations of SMF170AT1G.
What is the thermal resistance from junction to cathode (RθJcathode) for SMF170AT1G, and why does it matter?
SMF170AT1G has an RθJcathode of 26 °C/W, measured from silicon junction to cathode terminal. This low value enables efficient heat transfer to the PCB copper pour connected to the cathode pad - critical for sustaining repeated surges. When designing layout, engineers must ensure ≥100 mm² of 2-oz copper connected to the cathode to maintain safe junction temperatures below 150°C during burst-mode operation.
Is SMF170AT1G compliant with IEC61000−4−2 and IEC61000−4−4 standards?
Yes - SMF170AT1G is rated for IEC61000−4−2 Level 4 (±16 kV contact discharge) and IEC61000−4−4 (40 A, 5/50 ns ring wave), as confirmed in its official datasheet. These certifications mean the device alone satisfies the basic immunity requirements for end equipment without additional filtering, simplifying design validation for medical monitors, POS terminals, and industrial HMIs.
SMF170AT1G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Package/Case:
- SOD-123F
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 170V
- Voltage - Breakdown (Min):
- 189V
- Voltage - Clamping (Max) @ Ipp:
- 275V
- Current - Peak Pulse (10/1000µs):
- 600mA
- Power - Peak Pulse:
- 200W
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SOD-123FL
SMF170AT1G FAQ
1.How can I place an order for SMF170AT1G through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF170AT1G 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 SMF170AT1G reliable?
The price and inventory of SMF170AT1G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF170AT1G is usually 5 days.
3.What payment methods are accepted for SMF170AT1G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF170AT1G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF170AT1G?
SMF170AT1G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF170AT1G 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 SMF170AT1G?
For technical support, including SMF170AT1G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF170AT1G requirements.
6.How does Aetrix verify that SMF170AT1G is sourced from the original manufacturer or authorized distributors?
All SMF170AT1G 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 SMF170AT1G meets industry standards.
7.What is the process for return or replacement of SMF170AT1G?
All SMF170AT1G units undergo pre-shipment inspection (PSI). If there is an issue with SMF170AT1G, 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 SMF170AT1G part is unused and in its original packaging.
Return procedure for SMF170AT1G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF170AT1G 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
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