My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SMF18A-HM3-08
- Part No.:
- SMF18A-HM3-08
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-219AB
- Datasheet:
-
SMF18A-HM3-08.pdf
- Description:
- TVS DIODE 18VWM 29.2VC SMF
- Quantity:
- Payment:
- Shipping:
Inventory:25,463
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SMF18A-HM3-08 from Vishay Semiconductors is a unidirectional surface-mount ESD protection diode in DO-219AB (SOD-123W) package, designed for I/O line protection in high-speed digital interfaces. It features 18 V standoff voltage (VRWM), 29.2 V maximum 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 applications.
For engineers reviewing the SMF18A-HM3-08 datasheet, SMF18A-HM3-08 pinout, SMF18A-HM3-08 application, or SMF18A-HM3-08 equivalent, this device is selected for robust transient suppression in USB 2.0, HDMI, Ethernet PHY, and automotive infotainment data lines where low capacitance and fast response are critical to signal integrity.
Technical Context
The SMF18A-HM3-08 implements a planar silicon avalanche diode structure optimized for low incremental surge resistance and sub-nanosecond response time. Its unidirectional configuration provides reverse-biased clamping only, with cathode-anode polarity clearly marked on the SOD-123W body.
It operates across -65 °C to +175 °C junction temperature range and delivers 200 W peak pulse power (10/1000 μs waveform) with thermal resistance RthJA = 180 K/W on standard 3 mm × 3 mm Cu pads. The device meets AEC-Q101 stress test requirements including HBM > 8 kV and IEC 61000-4-2 ±30 kV contact/air discharge.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Standoff Voltage (VRWM) | 18 V - Maximum continuous reverse operating voltage before leakage exceeds 0.1 μA; sets minimum system operating margin for protected line. |
| Clamping Voltage (VC) | 29.2 V max at IPPM = 6.8 A - Peak voltage seen by downstream IC during 10/1000 μs surge; determines safe overvoltage headroom for connected logic. |
| Capacitance (CD) | 320 pF typ at 0 V, 1 MHz - Directly impacts signal rise/fall time degradation; suitable for ≤480 Mbps USB 2.0 but not USB 3.x or PCIe Gen2+. |
| ESD Rating | ±30 kV contact / ±30 kV air per IEC 61000-4-2 - Guarantees survivability against worst-case human-body ESD events without parametric shift or failure. |
| Package | DO-219AB (SOD-123W) - 3.9 mm × 1.9 mm × 1.08 mm low-profile outline compatible with automated SMT placement and reflow (peak 260 °C). |
| AEC-Q101 Qualified | Yes - Validated for automotive underhood and cabin applications requiring extended temperature cycling, humidity bias, and mechanical shock compliance. |
Pinout & Package
SMF18A-HM3-08 uses the DO-219AB (SOD-123W) surface-mount package: 3.9 mm length, 1.9 mm width, 1.08 mm height, with molded UL 94 V-0 compound and MSL level 1 rating. Cathode is marked by a bar on the top surface.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Anode | Input/Line side terminal | Connected to protected signal line; carries surge current into diode during overvoltage event. |
| Cathode | Ground reference terminal | Connected to system ground or low-impedance return path; defines clamping reference and enables unidirectional conduction. |
Key Features
| Feature | Design Value |
|---|---|
| Low clamping voltage | 29.2 V max at 6.8 A ensures downstream 3.3 V or 5 V logic remains within absolute maximum ratings during transients. |
| Fast response time | Sub-nanosecond turn-on enables effective suppression of ESD pulses with <1 ns rise time per IEC 61000-4-2. |
| Automotive-grade reliability | AEC-Q101 qualification confirms suitability for automotive ECUs, infotainment, and ADAS sensor interfaces. |
| Wave/reflow solderable | Compatible with standard Pb-free reflow profiles up to 260 °C peak, supporting high-volume manufacturing. |
Applications
| USB 2.0 Data Lines | HDMI DDC/CEC Channels |
|---|---|
|
Use Scenario: Protecting USB 2.0 D+ and D- lines in automotive head units and industrial docking stations from ESD events during cable insertion/removal. IC Role / Device Role: Unidirectional transient voltage suppressor placed between connector and USB transceiver IC. Use Value: 320 pF capacitance avoids signal integrity loss at 480 Mbps; 29.2 V clamping prevents damage to 3.3 V PHY inputs. |
Use Scenario: Safeguarding HDMI DDC (I²C) and CEC control lines in smart TVs and AV receivers against user-handling ESD. IC Role / Device Role: Low-capacitance ESD clamp on bidirectional control bus with pull-up resistors to 3.3 V or 5 V. Use Value: 18 V VRWM allows full compatibility with 5 V I²C buses; ±30 kV ESD rating exceeds IEC 61000-4-2 requirement. |
| Automotive Ethernet PHY Interfaces | Industrial RS-485 Transceivers |
|
Use Scenario: Protecting 100BASE-T1 automotive Ethernet PHY differential pairs in domain controllers and camera modules. IC Role / Device Role: Single-line ESD protection per signal (e.g., on TXP/TXN) referenced to chassis ground. Use Value: AEC-Q101 qualification ensures operation at -40 °C to +125 °C ambient; DO-219AB footprint supports dense PCB layouts. |
Use Scenario: Shielding RS-485 transceiver A/B lines in factory automation PLCs and motor drives from field-induced surges and ESD. IC Role / Device Role: Standoff-rated TVS diode placed between bus line and local ground, handling common-mode transients. Use Value: 200 W peak pulse power (10/1000 μs) withstands repetitive lightning-induced surges; 175 °C max junction temp supports harsh environments. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar ESD protection applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A-E3/57T | DO-214AC (SMA) package; 1.9 mm height vs. SMF18A-HM3-08's 1.08 mm; 350 pF capacitance vs. 320 pF; same 18 V VRWM and 29.2 V VC. | Larger footprint and higher profile limit use in ultra-thin consumer devices; better thermal dissipation for higher-duty-cycle surges. | Select SMAJ18A-E3/57T when board space permits and thermal management under repeated surges is prioritized over profile height. |
| TPD2E001DRYR | Monolithic dual-channel ESD array in SOT-553; 15 pF per channel; 5 V VRWM; integrated 10 Ω series resistors; not AEC-Q101 qualified. | Designed for high-speed data lines (USB 2.0, HDMI); unsuitable for 18 V systems or automotive underhood due to voltage and qualification limits. | Choose TPD2E001DRYR only for low-voltage, high-speed consumer interfaces where ultra-low capacitance is mandatory and automotive qualification is not required. |
Compared with SMAJ18A-E3/57T and TPD2E001DRYR, SMF18A-HM3-08 uniquely balances low profile (1.08 mm), automotive qualification, and 18 V standoff in a cost-effective discrete package-making it optimal for space-constrained automotive and industrial I/O protection where voltage rating and reliability are primary selection criteria.
Availability
SMF18A-HM3-08 is available at Aetrix Electronics and suitable for automotive infotainment, industrial RS-485 networks, and USB 2.0 peripheral interfaces requiring stable component supply and long-term lifecycle support.
Supply support for SMF18A-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 Intertechnology is a global manufacturer of discrete semiconductors and passive components, specializing in high-reliability solutions for automotive, industrial, and computing markets.
The SMF series targets compact, high-performance ESD protection for high-speed data lines in automotive and industrial systems, emphasizing AEC-Q101 compliance, low capacitance, and robust surge handling in minimal footprints.
FAQ
What is the maximum clamping voltage of SMF18A-HM3-08 at its rated peak pulse current?
The SMF18A-HM3-08 has a maximum reverse clamping voltage (VC) of 29.2 V at its rated peak pulse current (IPPM) of 6.8 A using a 10/1000 μs waveform. This value is measured per the Electrical Characteristics table in Vishay document 85881 Rev. 2.4 and defines the upper voltage limit imposed on protected circuitry during surge events.
Is SMF18A-HM3-08 qualified for automotive applications?
Yes, SMF18A-HM3-08 is AEC-Q101 qualified, as confirmed in the "FEATURES" section and "ABSOLUTE MAXIMUM RATINGS" table of Vishay's SMF5V0A to SMF58A datasheet (Rev. 2.4). It meets stress tests including human body model > 8 kV and IEC 61000-4-2 ±30 kV, making it suitable for automotive infotainment, ADAS, and body electronics.
What package type does SMF18A-HM3-08 use, and what are its key dimensions?
SMF18A-HM3-08 uses the DO-219AB (SOD-123W) package: 3.9 mm length, 1.9 mm width, and 1.08 mm maximum height. Its footprint recommendation is 2.9 mm × 1.4 mm, and it features a cathode bar marking. The package is UL 94 V-0 rated, MSL level 1, and compatible with Pb-free reflow up to 260 °C.
How does the capacitance of SMF18A-HM3-08 affect high-speed signal integrity?
With 320 pF typical capacitance at 0 V and 1 MHz, SMF18A-HM3-08 introduces measurable loading on high-speed lines. It is appropriate for USB 2.0 (480 Mbps) and RS-485 but not recommended for USB 3.x, HDMI 2.0, or PCIe Gen2+, where sub-2 pF devices are required to avoid signal attenuation and jitter.
What is the standoff voltage (VRWM) and why is it critical for SMF18A-HM3-08 placement?
The standoff voltage (VRWM) of SMF18A-HM3-08 is 18 V - the maximum continuous reverse voltage it can block without exceeding 0.1 μA leakage. This parameter dictates placement: it must be higher than the normal operating voltage of the protected line (e.g., 12 V automotive bus or 15 V industrial sensor output) to prevent false triggering while ensuring reliable clamping during overvoltage events.
SMF18A-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):
- 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 (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-219AB (SMF)
SMF18A-HM3-08 FAQ
1.How can I place an order for SMF18A-HM3-08 through Aetrix?
Please submit a Request for Quotation (RFQ) for SMF18A-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 SMF18A-HM3-08 reliable?
The price and inventory of SMF18A-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 SMF18A-HM3-08 is usually 5 days.
3.What payment methods are accepted for SMF18A-HM3-08?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SMF18A-HM3-08 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SMF18A-HM3-08?
SMF18A-HM3-08 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SMF18A-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 SMF18A-HM3-08?
For technical support, including SMF18A-HM3-08 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SMF18A-HM3-08 requirements.
6.How does Aetrix verify that SMF18A-HM3-08 is sourced from the original manufacturer or authorized distributors?
All SMF18A-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 SMF18A-HM3-08 meets industry standards.
7.What is the process for return or replacement of SMF18A-HM3-08?
All SMF18A-HM3-08 units undergo pre-shipment inspection (PSI). If there is an issue with SMF18A-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 SMF18A-HM3-08 part is unused and in its original packaging.
Return procedure for SMF18A-HM3-08:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SMF18A-HM3-08 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 …
