My Inquiry
My Account
Vishay SMF18A-HM3_A18
- Part No.:
- SMF18A-HM3_A18
- Manufacturer:
- Vishay
- Category:
- TVS Diodes
- Package:
- DO-219AB
- Datasheet:
-
SMF18A-HM3_A18.pdf
- Description:
- ESD PROTECTION DIODE SMF DO219AB
- Quantity:
- Payment:
- Shipping:
Inventory:5,629
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMF18A-HM3_A18 from Vishay Semiconductors is a unidirectional surface-mount ESD protection diode in DO-219AB (SOD-123W) package, designed for low-capacitance transient suppression on high-speed data lines. It features 18 V standoff voltage (VRWM), 29.2 V max clamping voltage at 6.8 A peak pulse current, 320 pF typical capacitance at 0 V, ±30 kV IEC 61000-4-2 ESD immunity, and AEC-Q101 qualification for automotive use.
For engineers reviewing the SMF18A-HM3_A18 datasheet, SMF18A-HM3_A18 pinout, SMF18A-HM3_A18 application, or SMF18A-HM3_A18 equivalent, this device is selected for robust electrostatic discharge protection in USB 2.0, HDMI, automotive infotainment interfaces, and industrial sensor signal conditioning where low clamping voltage and sub-1 ns response time are critical.
Technical Context
This diode operates as a unidirectional TVS (Transient Voltage Suppressor) with avalanche breakdown behavior, optimized for fast transient suppression on single-line signal paths. Its low incremental surge resistance ensures minimal voltage overshoot during 10/1000 μs surges, while its "Low Noise" technology enables sub-nanosecond response to ESD events per IEC 61000-4-2.
The SMF18A-HM3_A18 is rated for 200 W peak pulse power (10/1000 μs), 1000 W (8/20 μs), and supports continuous operation from –65 °C to +175 °C. It is qualified to AEC-Q101 with H3B-class ESD robustness (>8 kV HBM) and meets RoHS-compliant, lead-free termination requirements.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRWM) | 18 V - Maximum continuous reverse operating voltage before clamping begins; defines safe signal swing margin for 12–15 V nominal bus lines. |
| Clamping Voltage (VC) | 29.2 V max at IPPM = 6.8 A - Peak voltage seen by protected circuit during worst-case 10/1000 μs surge; ensures downstream ICs remain below absolute maximum ratings. |
| Capacitance (CD) | 320 pF at 0 V, 1 MHz - Low enough for USB 2.0 (480 Mbps) and CAN FD signal integrity; avoids excessive signal rise-time degradation. |
| ESD Rating | ±30 kV contact / ±30 kV air (IEC 61000-4-2) - Full system-level ESD immunity without external shielding or layout reinforcement. |
| Package | DO-219AB (SOD-123W) - 3.9 mm × 1.9 mm × 1.08 mm low-profile outline compatible with automated SMT assembly and reflow profiles up to 260 °C. |
| AEC-Q101 Qualified | Yes - Validated for automotive under-hood and infotainment applications requiring extended temperature cycling and reliability validation. |
| Peak Pulse Power | 200 W (10/1000 μs) - Sustains repeated transients in industrial control I/O without thermal runaway or parameter shift. |
Pinout & Package
SMF18A-HM3_A18 uses the DO-219AB (SOD-123W) surface-mount package: cathode-marked, single-diode configuration with two terminals. The package measures 3.9 mm length × 1.9 mm width × 1.08 mm height, features UL 94 V-0 molding compound, and is MSL Level 1 compliant.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Signal line input (protected side) | Connected to vulnerable trace (e.g., USB D+, HDMI TMDS+); conducts surge current toward ground when clamped. |
| Cathode | Ground reference / clamp return | Must be tied to low-inductance chassis or system ground plane; determines clamping threshold relative to ground potential. |
Key Features
| Feature | Design Value |
|---|---|
| Low clamping voltage | 29.2 V max at 6.8 A ensures protected ICs (e.g., USB PHYs with 30 V abs max) avoid overvoltage stress during surge events. |
| Sub-1 ns response time | "Low Noise" avalanche architecture enables clamping within <1 ns of ESD onset-critical for preserving signal edge integrity on high-speed lines. |
| AEC-Q101 qualification | Validated for automotive-grade reliability including temperature cycling, humidity bias, and mechanical shock-enabling use in ADAS camera links and infotainment displays. |
| Wave & reflow solderable | Compatible with standard Pb-free reflow profiles (peak ≤260 °C) and wave soldering; eliminates need for special thermal management during assembly. |
| Low profile footprint | DO-219AB package fits tight PCB real estate near connectors (e.g., micro-B USB ports) without interfering with adjacent components or shields. |
Applications
| Automotive Infotainment Display Interface | Industrial RS-485 Data Line Protection |
|---|---|
Use Scenario: Protecting LVDS or FPD-Link III video data lanes between head unit and TFT display in vehicles exposed to ESD during service or environmental charging. IC Role / Device Role / Timing Role: Unidirectional TVS diode placed directly at connector entry point to shunt ESD energy before reaching serializer/deserializer ICs. Use Value: 320 pF capacitance avoids skew between differential pairs; ±30 kV ESD rating eliminates need for secondary board-level shielding in cost-sensitive dash designs. |
Use Scenario: Safeguarding RS-485 transceivers in factory automation PLCs connected to long cable runs subject to lightning-induced surges and operator ESD. IC Role / Device Role / Timing Role: Standoff-clamp TVS on A/B differential lines, referenced to local ground, limiting transient voltage to <30 V during 10/1000 μs events. Use Value: 200 W peak pulse power rating sustains multiple surge events without degradation; DO-219AB package withstands vibration and thermal cycling in harsh enclosures. |
| USB 2.0 Host Port Protection | Medical Sensor Signal Conditioning |
Use Scenario: ESD protection on USB 2.0 D+/D− lines of portable diagnostic devices plugged/unplugged frequently in clinical environments. IC Role / Device Role / Timing Role: Bidirectional-capable unidirectional diode (cathode grounded) clamping both positive and negative transients on each line independently. Use Value: 29.2 V clamping voltage stays safely below USB PHY's 30 V absolute max rating; low capacitance preserves 480 Mbps eye diagram integrity. |
Use Scenario: Shielding analog front-end inputs of patient-worn biosensors (e.g., ECG leads) from handling ESD and electrostatic coupling in hospital settings. IC Role / Device Role / Timing Role: Low-leakage (0.1 μA @ 18 V) TVS placed before instrumentation amplifier input to prevent latch-up or offset shift. Use Value: 18 V VRWM allows full dynamic range for ±10 V sensor signals; AEC-Q101 qualification assures long-term parametric stability in life-critical monitoring. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ESD protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A-E3/5A (Vishay) | DO-214AC (SMA) package; 3.5 mm × 2.5 mm × 2.3 mm; higher thermal resistance (RthJA = 40°C/W vs. 180 K/W); 33.2 V VC at 6.5 A. | Less suitable for space-constrained layouts; lower power density limits use in high-repetition surge environments. | Select SMAJ18A-E3/5A only if legacy board design mandates SMA footprint or higher surge margin is needed beyond 200 W. |
| TPD2E001DRYR (TI) | 0402 dual-channel ESD array; 12 pF per line; 15 V VRWM; ±8 kV IEC 61000-4-2; not AEC-Q101 qualified. | Designed for ultra-high-speed digital interfaces (e.g., USB 3.0, MIPI); insufficient for automotive or industrial surge immunity. | Choose TPD2E001DRYR for compact, low-capacitance protection on consumer electronics; avoid for automotive or industrial applications requiring ±30 kV ESD or AEC-Q101 compliance. |
Compared with SMAJ18A-E3/5A and TPD2E001DRYR, SMF18A-HM3_A18 delivers optimal balance of low-profile packaging, automotive-grade reliability, and robust 200 W surge handling-making it the preferred choice for space-limited, high-reliability ESD protection where both size and ruggedness are non-negotiable.
Availability
SMF18A-HM3_A18 is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial RS-485 networks, and medical sensor interfaces requiring stable component supply across multi-year production cycles.
Supply support for SMF18A-HM3_A18 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 interface protection with optimized clamping, low capacitance, and AEC-Q101 qualification-designed specifically for ESD and surge resilience in automotive infotainment, industrial communications, and portable medical electronics.
FAQ
What is the standoff voltage and clamping voltage of SMF18A-HM3_A18?
The SMF18A-HM3_A18 has a maximum standoff voltage (VRWM) of 18 V and a maximum clamping voltage (VC) of 29.2 V at 6.8 A peak pulse current (10/1000 μs waveform). These values ensure reliable protection for 12–15 V nominal signal lines while keeping downstream ICs within their absolute maximum voltage ratings. The SMF18A-HM3_A18 maintains these parameters across its full operating temperature range of –65 °C to +175 °C.
Is SMF18A-HM3_A18 qualified for automotive applications?
Yes, SMF18A-HM3_A18 is AEC-Q101 qualified and rated for human body model (HBM) ESD >8 kV (Class H3B). It is validated for automotive under-hood and cabin environments, supporting applications such as infotainment display interfaces and ADAS camera links. The SMF18A-HM3_A18 also meets IEC 61000-4-2 ±30 kV contact and air discharge requirements, making it suitable for rigorous automotive EMC testing.
What package type does SMF18A-HM3_A18 use, and is it compatible with standard SMT processes?
SMF18A-HM3_A18 uses the DO-219AB (SOD-123W) package: 3.9 mm × 1.9 mm × 1.08 mm, with cathode marking and RoHS-compliant tin-plated terminations. It is fully compatible with standard Pb-free reflow soldering (peak ≤260 °C) and wave soldering processes. The SMF18A-HM3_A18 is MSL Level 1 per J-STD-020, eliminating bake requirements prior to assembly.
How does the capacitance of SMF18A-HM3_A18 affect high-speed signal integrity?
SMF18A-HM3_A18 has a typical capacitance of 320 pF at 0 V and 1 MHz. This value is carefully balanced to provide effective ESD clamping while maintaining acceptable signal integrity on moderate-speed interfaces like USB 2.0 (480 Mbps) and RS-485. The SMF18A-HM3_A18 avoids excessive rise-time degradation or reflection on these buses, unlike higher-capacitance alternatives that may distort eye diagrams or increase bit error rates.
Can SMF18A-HM3_A18 be used for bidirectional signal lines?
SMF18A-HM3_A18 is a unidirectional diode, but it can protect bidirectional lines (e.g., USB D+, RS-485 A) when configured with cathode tied to ground-clamping positive transients to ground and blocking negative transients via its high reverse breakdown voltage (20–22.3 V). For true bidirectional protection, two SMF18A-HM3_A18 devices in back-to-back configuration or a dedicated bidirectional TVS would be required. Each SMF18A-HM3_A18 must be applied per line.
SMF18A-HM3_A18 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay
- Package/Case:
- DO-219AB
- Series:
- eSMP®
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 18V
- Voltage - Breakdown (Min):
- 20V
- Voltage - Clamping (Max) @ Ipp:
- 29.2V
- Current - Peak Pulse (10/1000µs):
- 6.8A
- Power - Peak Pulse:
- 200W
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- 320pF @ 1MHz
- Operating Temperature:
- -65°C ~ 175°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-219AB (SMF)
SMF18A-HM3_A18 FAQ
1.How can I place an order for SMF18A-HM3_A18 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF18A-HM3_A18 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 SMF18A-HM3_A18 reliable?
The price and inventory of SMF18A-HM3_A18 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SMF18A-HM3_A18 is usually 5 days.
3.What payment methods are accepted for SMF18A-HM3_A18?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF18A-HM3_A18 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF18A-HM3_A18?
SMF18A-HM3_A18 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF18A-HM3_A18 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 SMF18A-HM3_A18?
For technical support, including SMF18A-HM3_A18 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF18A-HM3_A18 requirements.
6.How does Aetrix verify that SMF18A-HM3_A18 is sourced from the original manufacturer or authorized distributors?
All SMF18A-HM3_A18 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 SMF18A-HM3_A18 meets industry standards.
7.What is the process for return or replacement of SMF18A-HM3_A18?
All SMF18A-HM3_A18 units undergo pre-shipment inspection (PSI). If there is an issue with SMF18A-HM3_A18, 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 SMF18A-HM3_A18 part is unused and in its original packaging.
Return procedure for SMF18A-HM3_A18:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF18A-HM3_A18 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
Comparator circuit design covering voltage thresholds, input limits, open-collector outputs, LM393 wiring, op-amp differences, hysteresis, timing, window detection and practical fault diagnosis.
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 …
