My Inquiry
My Account
Vishay General Semiconductor - Diodes Division SM5S18AHM3/I
- Part No.:
- SM5S18AHM3/I
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-218AC
- Datasheet:
-
SM5S18AHM3/I.pdf
- Description:
- TVS DIODE 18VWM 29.2VC DO218AC
- Quantity:
- Payment:
- Shipping:
Inventory:6,242
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
SM5S18AHM3/I from Vishay General Semiconductor is a unidirectional surface-mount PAR® transient voltage suppressor in DO-218AB package, rated for 18 V stand-off voltage (VWM), 21.1 V nominal breakdown voltage (VBR), 3600 W peak pulse power (10/1000 μs), and 175 °C junction temperature. It delivers automotive-grade surge protection for load dump events in 12 V battery systems.
For engineers reviewing the SM5S18AHM3/I datasheet, SM5S18AHM3/I pinout, SM5S18AHM3/I application, or SM5S18AHM3/I equivalent, key selection criteria include unidirectional clamping behavior, AEC-Q101 qualification, ISO7637-2 compliance, low leakage (<10 μA at VWM), and thermal resistance RθJM = 0.45 °C/W for heatsink-mounted designs.
Technical Context
This TVS diode uses passivated anisotropic rectifier technology with junction passivation optimized for high-temperature stability. Its unidirectional polarity and heatsink-anode configuration enable direct mounting to metal chassis for efficient thermal dissipation under repetitive surge stress.
Designed for automotive load dump protection, it sustains 500 A peak forward surge current (8.3 ms half-sine) and maintains clamping voltage ≤29.2 V at 150 A IPPM. The device meets MSL Level 1 per J-STD-020 and operates across -55 °C to +175 °C junction range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VWM | 18.0 V - Maximum continuous reverse operating voltage before conduction begins; defines safe operating margin in 12 V automotive systems. |
| VBR (nom) | 21.1 V - Breakdown voltage at 5 mA test current; ensures reliable turn-on during transients exceeding system nominal voltage. |
| VC @ IPPM | 29.2 V - Clamping voltage at 150 A peak pulse current (10/1000 μs); limits downstream IC voltage stress during load dump. |
| PPPM (10/1000 μs) | 3600 W - Peak pulse power handling capacity; supports ISO7637-2 Pulse 5a load dump waveforms without failure. |
| TJ max | +175 °C - Maximum junction temperature rating; enables operation in engine bay environments with minimal derating. |
| RθJM | 0.45 °C/W - Junction-to-mount thermal resistance; confirms effective heat transfer to external heatsink when mounted per JEDEC 51-14. |
| ID @ VWM | <10 μA - Reverse leakage at 18 V stand-off; minimizes quiescent power loss in always-on vehicle modules. |
Pinout & Package
Package: DO-218AB - Surface-mount case with integral metal heatsink acting as anode terminal; RoHS-compliant, matte tin-plated leads, UL 94 V-0 molding compound.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Lead 1 (Anode) | Anode connection | Electrically connected to metal heatsink; must be soldered to PCB copper pour or chassis for thermal and electrical reference. |
| Lead 2 (Cathode) | Cathode connection | Standard signal-side terminal; connects to protected line (e.g., battery rail input) to clamp positive transients to ground. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualified | Validated for automotive electronics per stress test requirements including HTOL, TCT, and ESD; supports PPAP documentation. |
| ISO7637-2 compliant | Meets Pulse 5a load dump immunity up to 35 V/100 ms; verified under specified test conditions in datasheet Figure 3. |
| Junction passivation | Optimized die surface treatment reduces parameter drift over lifetime and improves reliability under high-humidity, high-TJ operation. |
| MSL Level 1 | Moisture sensitivity level 1 per J-STD-020; allows unlimited floor life and reflow at peak 245 °C without popcorn risk. |
| Low VF at high IF | Max 2.0 V forward voltage at 100 A (300 μs pulse); minimizes conduction loss during bidirectional surge events with reverse recovery. |
Applications
| Automotive Load Dump Protection | Engine Control Unit (ECU) Power Input |
|---|---|
Use Scenario: Protecting 12 V battery-fed circuits during alternator load dump events (ISO7637-2 Pulse 5a). IC Role / Device Role / Timing Role: Unidirectional TVS clamping device placed between battery rail and DC/DC converter input. Use Value: Limits transient voltage to ≤29.2 V at 150 A, preventing damage to downstream PMICs and microcontrollers rated for 36 V absolute max. |
Use Scenario: Safeguarding power inputs of engine control units exposed to cranking transients and ignition noise. IC Role / Device Role / Timing Role: Primary overvoltage suppression element on main 12 V supply line upstream of input filter capacitors. Use Value: Withstands 500 A surge (8.3 ms half-sine) and operates continuously at TJ = 175 °C, enabling placement near hot engine compartments. |
| Body Control Module (BCM) Power Rail | Advanced Driver Assistance Systems (ADAS) Camera Power |
Use Scenario: Securing power distribution nodes in body electronics managing lighting, door locks, and HVAC. IC Role / Device Role / Timing Role: Standoff-rated TVS (VWM = 18 V) ensuring no conduction during normal 13.5–14.5 V charging, only activating on >21.1 V surges. Use Value: Leakage <10 μA at VWM preserves low-power sleep mode current budgets; DO-218AB heatsink enables compact layout without discrete thermal pads. |
Use Scenario: Protecting 12 V input of ADAS front-facing cameras subject to vibration-induced arcing and ESD coupling. IC Role / Device Role / Timing Role: Fast-response clamping device with 10/1000 μs waveform capability, placed adjacent to connector entry point. Use Value: 3600 W peak power rating handles coupled lightning-induced surges; AEC-Q101 qualification ensures long-term field reliability in safety-critical vision systems. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar unidirectional TVS diode applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18AHE3_A/H | DO-214AC package, lower PPPM (400 W), higher RθJA (65 °C/W), same VWM/VBR range. | Limited to lower-energy transients; unsuitable for ISO7637-2 Pulse 5a without parallel staging. | Select SMAJ18AHE3_A/H only for cost-sensitive non-automotive applications where surge energy ≤400 W. |
| SM5S18AHM3 | Identical electrical specs and DO-218AB package; differs only in packaging - SM5S18AHM3/I uses I-tape/reel (750 pcs), SM5S18AHM3 uses standard reel. | No functional or application difference; both meet AEC-Q101 and ISO7637-2. | SM5S18AHM3/I is preferred for automated SMT lines requiring indexed tape; SM5S18AHM3 suits manual or bulk-feed assembly. |
Compared with SMAJ18AHE3_A/H and SM5S18AHM3, the SM5S18AHM3/I provides superior thermal performance (RθJM = 0.45 °C/W vs. no heatsink path), full load dump capability (3600 W), and guaranteed AEC-Q101 qualification - making it the only option among the three validated for under-hood automotive deployment.
Availability
SM5S18AHM3/I is available at Aetrix Electronics and suitable for automotive load dump protection, engine control unit (ECU) power input hardening, and body control module (BCM) power rail stabilization requiring stable component supply and long-term lifecycle support.
Supply support for SM5S18AHM3/I 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 General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, TVS devices, and power MOSFETs for industrial, automotive, and computing markets.
The SM5SxxA family was engineered specifically for high-reliability automotive transient suppression, emphasizing thermal robustness (TJ = 175 °C), AEC-Q101 compliance, and ISO7637-2 Pulse 5a capability in surface-mount form factor.
FAQ
What is the clamping voltage of the SM5S18AHM3/I at its rated peak pulse current?
The SM5S18AHM3/I has a maximum clamping voltage (VC) of 29.2 V at 150 A peak pulse current with a 10/1000 μs waveform. This value is measured per standard test conditions in the Vishay datasheet and ensures downstream components see limited overvoltage during automotive load dump events. The SM5S18AHM3/I maintains this clamping performance across its full operating temperature range.
Is the SM5S18AHM3/I qualified for automotive use?
Yes, the SM5S18AHM3/I is AEC-Q101 qualified and explicitly designed for automotive applications. It meets ISO7637-2 load dump requirements, operates from -55 °C to +175 °C, and is manufactured with process controls required for PPAP submission. The "H" in the part number denotes AEC-Q101 qualification, and the "I" suffix indicates 750-piece tape-and-reel packaging optimized for SMT production of the SM5S18AHM3/I.
What does the "HM3/I" suffix mean in SM5S18AHM3/I?
In SM5S18AHM3/I, "H" indicates AEC-Q101 qualification, "M3" denotes the DO-218AB package with matte tin plating and JESD201 Class 2 whisker resistance, and "I" specifies the preferred packaging: 13-inch diameter plastic tape and reel with 750 units per reel, anode oriented toward sprocket holes. This full suffix confirms the SM5S18AHM3/I meets automotive reliability, thermal, and assembly requirements.
Can the SM5S18AHM3/I replace older SM5S18A variants?
The SM5S18AHM3/I replaces legacy SM5S18A versions with enhanced reliability: it includes AEC-Q101 qualification ("H"), DO-218AB package with improved thermal path ("M3"), and RoHS-compliant lead finish. Electrical parameters (VWM = 18 V, VBR = 21.1 V, VC = 29.2 V) remain identical. Designers should verify mechanical footprint compatibility, as DO-218AB differs from earlier DO-218 packages used in pre-HM3 variants of the SM5S18AHM3/I.
What is the thermal resistance from junction to mount (RθJM) for the SM5S18AHM3/I?
The SM5S18AHM3/I has a typical junction-to-mount thermal resistance (RθJM) of 0.45 °C/W, measured per JEDEC 51-14 using the Transient Dual Interface Method. This low value reflects the integral metal heatsink design of the DO-218AB package and requires mounting the anode (heatsink) directly to a thermally conductive plane or chassis. Proper mounting is essential to achieve the full 3600 W surge rating of the SM5S18AHM3/I.
SM5S18AHM3/I Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-218AC
- Series:
- PAR®
- 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):
- 123A
- Power - Peak Pulse:
- 3600W (3.6kW)
- Power Line Protection:
- No
- Applications:
- -
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 175°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-218AC
SM5S18AHM3/I FAQ
1.How can I place an order for SM5S18AHM3/I through Aetrix?
Please submit a Request for Quotation (RFQ) for SM5S18AHM3/I 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 SM5S18AHM3/I reliable?
The price and inventory of SM5S18AHM3/I are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for SM5S18AHM3/I is usually 5 days.
3.What payment methods are accepted for SM5S18AHM3/I?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for SM5S18AHM3/I transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for SM5S18AHM3/I?
SM5S18AHM3/I orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your SM5S18AHM3/I 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 SM5S18AHM3/I?
For technical support, including SM5S18AHM3/I datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your SM5S18AHM3/I requirements.
6.How does Aetrix verify that SM5S18AHM3/I is sourced from the original manufacturer or authorized distributors?
All SM5S18AHM3/I 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 SM5S18AHM3/I meets industry standards.
7.What is the process for return or replacement of SM5S18AHM3/I?
All SM5S18AHM3/I units undergo pre-shipment inspection (PSI). If there is an issue with SM5S18AHM3/I, 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 SM5S18AHM3/I part is unused and in its original packaging.
Return procedure for SM5S18AHM3/I:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
SM5S18AHM3/I 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
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 …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
