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Diodes Incorporated SMF4L8.5A-7
- Part No.:
- SMF4L8.5A-7
- Manufacturer:
- Diodes Incorporated
- Category:
- TVS Diodes
- Package:
- DO-219AA
- Datasheet:
-
SMF4L8.5A-7.pdf
- Description:
- TRANSIENT VOLTAGE SUPPRESSOR PP
- Quantity:
- Payment:
- Shipping:
Inventory:9,820
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Product details
Overview
SMF4L8.5A-7 from Diodes Incorporated is a unidirectional 400W surface-mount transient voltage suppressor (TVS) designed for robust overvoltage protection in low-voltage DC power rails. It features a working peak reverse voltage of 8.5V, minimum breakdown voltage of 9.44V at 1mA, maximum clamping voltage of 14.4V at 27.7A, and <10μA reverse leakage at VRWM - deployed in automotive battery contacts and industrial power management circuits.
For engineers reviewing the SMF4L8.5A-7 datasheet, SMF4L8.5A-7 pinout, SMF4L8.5A-7 application, or SMF4L8.5A-7 equivalent, key selection criteria include clamping performance under 10/1000µs surge, unidirectional polarity confirmation via cathode band marking, DO-219AA package thermal resistance (RθJA = 96°C/W), and IEC61000-4-2 ±30kV ESD compliance.
Technical Context
This TVS diode operates as a unidirectional clamp, activating when reverse voltage exceeds its 9.44V–10.43V breakdown range to divert transients away from sensitive downstream circuitry. Its fast response time (<1.0ns from 0V to VBR) ensures protection against ESD and lightning-induced surges before IC damage occurs.
The device sustains 400W peak pulse power (10/1000µs waveform) with a maximum clamping voltage of 14.4V at 27.7A, enabling effective suppression on 12V automotive and 9V industrial supply lines. Thermal design leverages a low RθJC of 18°C/W and junction-to-solder-point resistance of 70°C/W for reliable operation up to +175°C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power | 400W (10/1000µs waveform); supports high-energy surge events without failure |
| Working Peak Reverse Voltage (VRWM) | 8.5V; sets maximum continuous operating voltage before clamping initiates |
| Breakdown Voltage (VBR) | 9.44V min / 10.43V max @ 1mA; defines precise turn-on threshold for transient detection |
| Maximum Clamping Voltage (VC) | 14.4V @ 27.7A IPP; limits protected circuit voltage during worst-case surge |
| Reverse Leakage Current | 10μA @ 8.5V; ensures minimal standby power loss in always-on systems |
| ESD Withstand | ±30kV air / ±30kV contact per IEC61000-4-2; qualifies for harsh handling environments |
| Response Time | <1.0ns (unidirectional); enables sub-nanosecond reaction to fast-rising ESD events |
Pinout & Package
Package: DO-219AA surface-mount molded plastic case (UL 94V-0), 2.80mm × 1.90mm footprint, 3.80mm height, 0.016g weight. Cathode band denotes unidirectional polarity; terminals are matte tin-finished copper alloy leads.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Low-side reference terminal | Connected to ground or lowest potential node; completes clamping path during overvoltage |
| Cathode | High-side surge input terminal | Connected to protected line (e.g., battery rail); cathode band identifies polarity for correct PCB orientation |
Key Features
| Feature | Design Value |
|---|---|
| 400W peak pulse rating | Enables single-device protection against ISO 7637-2 Pulse 1/2a/5a surges in 12V automotive systems |
| DO-219AA ultra-compact package | Reduces PCB area by >30% vs. SMA while maintaining 1.0W steady-state dissipation capability |
| IEC61000-4-2 ±30kV ESD rating | Eliminates need for external ESD diodes in USB, CAN, or sensor interface ports |
| Lead-free, halogen-free "Green" construction | Meets RoHS 3 (2015/863/EU) and automotive AEC-Q200 requirements without derating |
| Fast <1.0ns response time | Protects high-speed logic and microcontrollers from nanosecond-scale ESD transients |
Applications
| Automotive Battery Protection | Industrial Power Input Stage |
|---|---|
Use Scenario: 12V battery feed line in engine control units exposed to load dump and jump-start transients. IC Role / Device Role / Timing Role: Unidirectional TVS clamp placed between battery connector and DC-DC converter input. Use Value: Limits voltage to ≤14.4V during 27.7A surge, preventing MOSFET gate oxide rupture and regulator latch-up. |
Use Scenario: 9V auxiliary power rail in programmable logic controllers subject to inductive switching noise. IC Role / Device Role / Timing Role: Primary overvoltage protector upstream of LDO regulators and microcontroller power pins. Use Value: Clamps 10/1000µs surges within 1ns, preserving 3.3V logic integrity without adding series impedance. |
| USB-C Port ESD Protection | Smart Sensor Node Power Rail |
Use Scenario: VBUS line in automotive infotainment USB-C receptacles subjected to repeated hot-plug ESD events. IC Role / Device Role / Timing Role: Standalone unidirectional TVS on VBUS, positioned before USB power delivery controller. Use Value: Withstands ±30kV contact discharge without degradation, maintaining 8.5V standoff for clean 5V/9V PD negotiation. |
Use Scenario: 3.3V power supply for MEMS accelerometers and BLE radios in predictive maintenance edge nodes. IC Role / Device Role / Timing Role: Low-leakage (10μA) TVS on sensor rail to avoid bias current interference while enabling field ESD resilience. Use Value: Prevents false triggers and ADC offset shifts caused by 8kV system-level ESD coupling into analog front-end. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ8.5A | Same VRWM (8.5V) but lower PPK (400W same), larger SMA package (RθJA = 110°C/W) | Less suitable for space-constrained automotive modules; higher thermal resistance requires larger copper pour | Choose if legacy board layout uses SMA footprints and thermal margin ≥15°C exists |
| SMF4L8.5CA | Bidirectional variant; identical VRWM, VBR, VC, but symmetric clamping for AC-coupled lines | Required only where bidirectional transients exist (e.g., RS-485, CAN bus); adds unnecessary cost for DC rails | Use only when protecting differential or floating signal lines - not for standard DC power rails |
Compared with SMAJ8.5A, SMF4L8.5A-7 saves 35% board area and improves thermal performance; versus SMF4L8.5CA, it avoids over-specification for unidirectional DC protection while reducing leakage by 50%.
Availability
SMF4L8.5A-7 is available at Aetrix Electronics and suitable for automotive battery protection, industrial power input stages, USB-C port ESD protection, and smart sensor node power rails requiring stable component supply across production lifecycles.
Supply support for SMF4L8.5A-7 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
Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, specializing in high-reliability protection, signal integrity, and power management solutions.
The SMF4L series belongs to Diodes' high-power surface-mount TVS portfolio, engineered specifically for AEC-Q200-compliant automotive and industrial applications demanding compact size, low leakage, and repeatable clamping performance.
FAQ
What is the polarity configuration of SMF4L8.5A-7?
The SMF4L8.5A-7 is a unidirectional TVS diode, identified by a visible cathode band on the DO-219AA package. This configuration allows conduction only during reverse-biased overvoltage events, making it ideal for DC power rail protection where forward conduction must be blocked.
Does SMF4L8.5A-7 meet automotive qualification standards?
Yes - SMF4L8.5A-7 is manufactured in IATF 16949-certified facilities and qualified to AEC-Q200 for passive components. It meets JEDEC reliability standards referenced in AEC-Q and supports PPAP documentation for automotive Tier 1 suppliers.
How does the DO-219AA package affect thermal performance?
The DO-219AA package delivers RθJA = 96°C/W (on 1"×1" FR-4 with 2 oz. Cu), significantly better than SMA alternatives. Its low RθJC = 18°C/W and RθJS = 70°C/W enable efficient heat transfer to the PCB, supporting sustained operation at +175°C junction temperature.
Can SMF4L8.5A-7 replace older SMAJ-series TVS diodes?
Yes - SMF4L8.5A-7 provides identical electrical specs (VRWM, VBR, VC, PPK) in a 35% smaller DO-219AA package with improved thermal resistance. Layout redesign is required due to different pad dimensions, but no circuit revalidation is needed for DC rail protection roles.
SMF4L8.5A-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- DO-219AA
- Series:
- SMF4L
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 8.5V
- Voltage - Breakdown (Min):
- 9.44V
- Voltage - Clamping (Max) @ Ipp:
- 14.4V
- Current - Peak Pulse (10/1000µs):
- 27.7A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-219AA
SMF4L8.5A-7 FAQ
1.How can I place an order for SMF4L8.5A-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF4L8.5A-7 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 SMF4L8.5A-7 reliable?
The price and inventory of SMF4L8.5A-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF4L8.5A-7 is usually 5 days.
3.What payment methods are accepted for SMF4L8.5A-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF4L8.5A-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF4L8.5A-7?
SMF4L8.5A-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF4L8.5A-7 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 SMF4L8.5A-7?
For technical support, including SMF4L8.5A-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF4L8.5A-7 requirements.
6.How does Aetrix verify that SMF4L8.5A-7 is sourced from the original manufacturer or authorized distributors?
All SMF4L8.5A-7 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 SMF4L8.5A-7 meets industry standards.
7.What is the process for return or replacement of SMF4L8.5A-7?
All SMF4L8.5A-7 units undergo pre-shipment inspection (PSI). If there is an issue with SMF4L8.5A-7, 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 SMF4L8.5A-7 part is unused and in its original packaging.
Return procedure for SMF4L8.5A-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF4L8.5A-7 Tags
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ESD9B5.0ST5G
onsemi
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DESD3V3E1BL-7B
Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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Diodes Incorporated
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onsemi
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Diodes Incorporated
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Diodes Incorporated
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Nexperia USA Inc.
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Toshiba Semiconductor and Storage
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Diodes Incorporated
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