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Vishay General Semiconductor - Diodes Division SMF40A-HM3-08
- Part No.:
- SMF40A-HM3-08
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-219AB
- Datasheet:
-
SMF40A-HM3-08.pdf
- Description:
- TVS DIODE 40VWM 64.5VC SMF
- Quantity:
- Payment:
- Shipping:
Inventory:27,565
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Product details
Overview
SMF40A-HM3-08 from Vishay Semiconductors is a unidirectional surface-mount ESD protection diode in the SMF (DO-219AB) package, designed for transient voltage suppression in high-speed data lines and power rails. It features a 40 V stand-off voltage (VRWM), 44.4–49.1 V reverse breakdown range (VBR), 64.5 V maximum clamping voltage at 3.1 A peak pulse current (VC), 172 pF typical capacitance at 0 V, and ±30 kV IEC 61000-4-2 ESD immunity.
For engineers reviewing the SMF40A-HM3-08 datasheet, SMF40A-HM3-08 pinout, SMF40A-HM3-08 application, or SMF40A-HM3-08 equivalent, this device is selected for robust electrostatic discharge protection in automotive infotainment interfaces, USB 2.0 signal lines, and industrial sensor I/O where low clamping voltage, fast response, and AEC-Q101 qualification are required.
Technical Context
This unidirectional TVS diode operates as a shunt-type transient suppressor, conducting only when reverse voltage exceeds its breakdown threshold to clamp surges toward ground. Its low incremental surge resistance ensures minimal voltage overshoot during fast transients, while "Low Noise" technology enables sub-nanosecond response time critical for protecting high-bandwidth analog and digital signals.
The device complies with AEC-Q101 for automotive use and meets IEC 61000-4-2 (±30 kV contact/air) and IEC 61000-4-5 (1000 W, 8/20 μs) standards. Its SOD-123W-compatible DO-219AB package supports wave and reflow soldering, with MSL level 1 rating and peak reflow temperature up to 260 °C.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Stand-off Voltage (VRWM) | 40 V - Maximum continuous reverse operating voltage before conduction begins; defines safe operating margin for 36 V nominal systems. |
| Breakdown Voltage (VBR) | 44.4–49.1 V at 1 mA - Confirmed reverse avalanche onset range; ensures reliable triggering above system rail tolerances. |
| Clamping Voltage (VC) | 64.5 V at 3.1 A (10/1000 μs) - Peak voltage seen by protected circuit during surge; limits stress on downstream ICs. |
| Capacitance (CD) | 172 pF at 0 V, 1 MHz - Low enough for USB 2.0 (480 Mbps) signal integrity without excessive rise-time degradation. |
| ESD Rating | ±30 kV contact / ±30 kV air per IEC 61000-4-2 - Full compliance with highest industrial and automotive ESD test levels. |
| Peak Pulse Power | 200 W (10/1000 μs), 1000 W (8/20 μs) - Handles repetitive ESD events and lightning-induced surges in compact footprint. |
| Operating Temp Range | −65 °C to +175 °C - Supports under-hood automotive and wide-temperature industrial deployments. |
Pinout & Package
SMF40A-HM3-08 uses the DO-219AB (SMF) package: low-profile, surface-mount, single-diode configuration with cathode marking bar. Dimensions: 3.9 mm × 1.9 mm × 1.08 mm (L × W × H). Compatible with SOD-123W, SOD-123F, and SOD-123FL footprints.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Input/Line side | Connected to signal or power line requiring protection; conducts surge current toward cathode (ground path). |
| Cathode | Ground reference | Connected to system ground plane; establishes clamping reference and provides low-impedance return for transient energy. |
Key Features
| Feature | Design Value |
|---|---|
| 200 W peak pulse power (10/1000 μs) | Enables repeated ESD event handling without degradation in space-constrained PCB layouts. |
| ±30 kV IEC 61000-4-2 ESD immunity | Meets highest-level system-level ESD testing for automotive and industrial end equipment certification. |
| AEC-Q101 qualified | Validated for automotive-grade reliability including HTOL, temperature cycling, and mechanical shock per AEC standard. |
| Low clamping voltage (64.5 V @ 3.1 A) | Reduces voltage overshoot across protected ICs, improving survival rate of sensitive 3.3 V/5 V interface receivers. |
| 172 pF capacitance at 0 V | Preserves signal edge integrity on 480 Mbps USB 2.0 and CAN FD lines without added jitter or attenuation. |
Applications
| Automotive Infotainment Display Interface | Industrial RS-485 Communication Port |
|---|---|
|
Use Scenario: Protecting LVDS or FPD-Link III video data lines between head unit and TFT display against ESD from user touch and harness coupling. IC Role / Device Role / Timing Role: Unidirectional shunt TVS diode placed differential-pair adjacent to connector, clamping transients before they reach serializer/deserializer ICs. Use Value: Prevents display flicker, pixel corruption, or reset events caused by ±30 kV contact discharge on exposed cables or bezels. |
Use Scenario: Safeguarding RS-485 transceivers in factory automation PLC I/O modules exposed to motor drive noise and field wiring ESD. IC Role / Device Role / Timing Role: Line-side TVS on A/B bus lines, referenced to local ground, absorbing common-mode surges induced by nearby 48 V DC power switching. Use Value: Maintains communication uptime by preventing transceiver latch-up or permanent damage during maintenance hot-plug events. |
| USB 2.0 Host Port Protection | Automotive CAN FD Node Protection |
|
Use Scenario: ESD hardening of D+/D− lines on USB 2.0 ports in telematics control units (TCUs) and docking stations. IC Role / Device Role / Timing Role: Dual-channel (single-diode per line) unidirectional TVS, mounted within 5 mm of USB connector, minimizing inductance in clamping path. Use Value: Ensures full-speed USB enumeration remains functional after repeated ±30 kV air discharge events during vehicle service. |
Use Scenario: Transient suppression on CAN_H/CAN_L lines in ADAS domain controllers subjected to battery load dump and ESD in chassis-grounded environments. IC Role / Device Role / Timing Role: Bidirectional-capable unidirectional pair (two SMF40A-HM3-08 devices) referenced to chassis ground, clamping both positive and negative transients. Use Value: Avoids CAN bus error frames or node resets during door-closing ESD or alternator ripple coupling into harnesses. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ESD protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ40A-E3/57T | DO-214AC (SMA) package; 64.5 V VC same, but 2.5× larger footprint and 220 pF capacitance. | Higher parasitic capacitance limits use to ≤12 Mbps interfaces; less suitable for USB 2.0 or CAN FD. | Select SMAJ40A-E3/57T only if board space allows larger package and lower-speed signaling is acceptable. |
| TPD2E001DRYR | Monolithic dual-channel ESD array in SOT-553; 15 pF per line, but 12 V VRWM and 21 V VC - not rated for 40 V systems. | Designed for 3.3 V logic I/O; insufficient stand-off for 24–48 V automotive power-rail protection. | Choose TPD2E001DRYR only for low-voltage data lines (e.g., I²C, UART); not a system-level replacement for SMF40A-HM3-08. |
Compared with SMAJ40A-E3/57T and TPD2E001DRYR, SMF40A-HM3-08 uniquely balances 40 V stand-off, 172 pF capacitance, and DO-219AB size-making it optimal for compact, high-reliability 24–48 V automotive and industrial data interfaces where both voltage margin and signal fidelity matter.
Availability
SMF40A-HM3-08 is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial RS-485 networks, and USB 2.0 host port protection requiring stable component supply, AEC-Q101 qualification, and consistent DO-219AB packaging.
Supply support for SMF40A-HM3-08 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
Vishay Semiconductors is a global leader in discrete semiconductors, specializing in high-reliability diodes, MOSFETs, optoelectronics, and passive components for automotive, industrial, and computing markets.
The SMF series targets high-speed, high-surge ESD protection in space-constrained applications, with design focus on AEC-Q101 compliance, low clamping, and compatibility with modern SMT assembly processes.
FAQ
What is the maximum clamping voltage of SMF40A-HM3-08 under standard test conditions?
The SMF40A-HM3-08 has a maximum clamping voltage (VC) of 64.5 V when subjected to a 10/1000 μs waveform at 3.1 A peak pulse current. This value is measured per IEC 61000-4-5 and defines the upper voltage limit imposed on protected circuits during surge events. The clamping performance is guaranteed across the full operating temperature range of −65 °C to +175 °C, making SMF40A-HM3-08 suitable for under-hood automotive applications.
Is SMF40A-HM3-08 qualified to AEC-Q101, and what does that mean for automotive use?
Yes, SMF40A-HM3-08 is AEC-Q101 qualified, meaning it has passed stress tests including high-temperature operating life (HTOL), temperature cycling, mechanical shock, and ESD (HBM >8 kV). This qualification confirms suitability for automotive electronic modules where reliability under thermal, vibration, and electrical stress is mandatory. SMF40A-HM3-08 is commonly deployed in TCUs, body control modules, and ADAS sensors where failure could impact safety or functionality.
How does the 172 pF capacitance of SMF40A-HM3-08 affect high-speed signal integrity?
The 172 pF typical capacitance at 0 V and 1 MHz makes SMF40A-HM3-08 compatible with USB 2.0 (480 Mbps) and CAN FD (5 Mbps) interfaces when placed with short trace lengths (<5 mm) and proper grounding. While higher than some low-capacitance arrays, this value avoids excessive signal rise-time degradation or reflection-verified in Vishay's application notes for FPD-Link III and RS-485 designs using SMF40A-HM3-08.
What is the package type and soldering compatibility of SMF40A-HM3-08?
SMF40A-HM3-08 uses the DO-219AB (SMF) package-a low-profile, surface-mount outline identical to SOD-123W, with dimensions 3.9 mm × 1.9 mm × 1.08 mm. It is fully compatible with standard reflow soldering profiles, rated for peak temperatures up to 260 °C, and classified as MSL level 1 (unlimited floor life). The cathode is marked by a bar on the top surface, and orientation in tape follows EIA-481 standard for automated placement.
Can SMF40A-HM3-08 be used for bidirectional protection, and how is that implemented?
SMF40A-HM3-08 is a unidirectional TVS diode, but bidirectional protection can be achieved by placing two devices in series–opposed configuration (anode-to-anode or cathode-to-cathode) across the line. This method delivers symmetrical clamping for both polarities while retaining the 40 V VRWM and 64.5 V VC ratings per direction. Vishay validates this topology for CAN FD and LIN bus protection in technical note AN1005, confirming robustness against ±30 kV ESD in either polarity.
SMF40A-HM3-08 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-219AB
- Series:
- eSMP®
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 40V
- Voltage - Breakdown (Min):
- 44.4V
- Voltage - Clamping (Max) @ Ipp:
- 64.5V
- Current - Peak Pulse (10/1000µs):
- 3.1A
- Power - Peak Pulse:
- 200W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- 172pF @ 1MHz
- Operating Temperature:
- -65°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-219AB (SMF)
SMF40A-HM3-08 FAQ
1.How can I place an order for SMF40A-HM3-08 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF40A-HM3-08 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 SMF40A-HM3-08 reliable?
The price and inventory of SMF40A-HM3-08 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF40A-HM3-08 is usually 5 days.
3.What payment methods are accepted for SMF40A-HM3-08?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF40A-HM3-08 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF40A-HM3-08?
SMF40A-HM3-08 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF40A-HM3-08 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 SMF40A-HM3-08?
For technical support, including SMF40A-HM3-08 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF40A-HM3-08 requirements.
6.How does Aetrix verify that SMF40A-HM3-08 is sourced from the original manufacturer or authorized distributors?
All SMF40A-HM3-08 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 SMF40A-HM3-08 meets industry standards.
7.What is the process for return or replacement of SMF40A-HM3-08?
All SMF40A-HM3-08 units undergo pre-shipment inspection (PSI). If there is an issue with SMF40A-HM3-08, 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 SMF40A-HM3-08 part is unused and in its original packaging.
Return procedure for SMF40A-HM3-08:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF40A-HM3-08 Tags
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