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Vishay General Semiconductor - Diodes Division P4SMA18AHM3_A/I
- Part No.:
- P4SMA18AHM3_A/I
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Category:
- TVS Diodes
- Package:
- DO-214AC, SMA
- Datasheet:
-
P4SMA18AHM3_A/I.pdf
- Description:
- TVS DIODE 15.3VWM 25.2VC DO214AC
- Quantity:
- Payment:
- Shipping:
Inventory:4,420
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Product details
Overview
P4SMA18AHM3_A/I from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMA (DO-214AC) package, rated for 18 V breakdown voltage (VBR = 17.1–18.9 V at 1 mA), 15.3 V standoff voltage (VWM), and 25.2 V clamping voltage (VC) at 15.9 A peak pulse current (IPPM). It delivers 400 W peak pulse power (10/1000 µs waveform) and is AEC-Q101 qualified for automotive-grade transient protection on power rails and signal lines.
For engineers reviewing the P4SMA18AHM3_A/I datasheet, P4SMA18AHM3_A/I pinout, P4SMA18AHM3_A/I application, or P4SMA18AHM3_A/I equivalent, this device is selected for robust overvoltage protection in automotive ECUs, industrial sensor interfaces, and DC power input stages where low clamping voltage, fast response (<1 ns), and halogen-free RoHS compliance are required.
Technical Context
The P4SMA18AHM3_A/I operates as a unidirectional avalanche diode with glass-passivated junction, enabling sub-nanosecond response to ESD and surge transients. Its clamping behavior is defined by a 25.2 V maximum VC at 15.9 A IPPM, with thermal resistance RθJA = 120 °C/W and RθJL = 30 °C/W under standard PCB mounting (0.2" × 0.2" copper pads).
It supports repetitive surge duty cycles up to 0.01 %, derates linearly above TA = 25 °C per Fig. 2, and meets MSL Level 1 (peak reflow 260 °C). The cathode band denotes polarity; no marking is used for bidirectional variants - but this part is explicitly unidirectional per ordering code "A" and marking "18A".
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VBR (min/max) | 17.1 V / 18.9 V at IT = 1 mA - defines precise avalanche initiation threshold for reliable overvoltage triggering |
| VWM | 15.3 V - maximum continuous reverse operating voltage before leakage exceeds 1 µA |
| VC @ IPPM | 25.2 V at 15.9 A - clamped voltage during 10/1000 µs surge, limiting downstream IC stress |
| PPPM | 400 W - peak transient power handling capability under standardized surge waveform |
| IFSM | 40 A - single half-sine surge rating (8.3 ms), supporting inrush and load-dump immunity |
| TJ max. | +150 °C - maximum junction temperature, enabling operation in under-hood automotive environments |
| Package | SMA (DO-214AC) - industry-standard SMD outline with 5.28 mm × 4.50 mm footprint and matte tin-plated leads |
Pinout & Package
SMA (DO-214AC) package: surface-mount, two-terminal, molded epoxy case with cathode band marking. Terminals are matte tin-plated, solderable per J-STD-002 and JESD 22-B102. Polarity: cathode end marked with band; anode unmarked.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (banded end) | Transient current sink node | Connected to protected line; conducts surge current to ground when VLINE > VBR |
| Anode (unmarked end) | Reference/return node | Typically tied to system ground or low-impedance return path for clamping action |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q101 qualification | Validated for automotive applications including engine control, body electronics, and ADAS sensors |
| Halogen-free & RoHS-compliant (HM3 suffix) | Meets global environmental regulations without compromising surge robustness or thermal performance |
| 400 W peak pulse power (10/1000 µs) | Withstands high-energy transients common in 12 V/24 V vehicle electrical systems |
| Low incremental surge resistance | Minimizes VC overshoot during fast-rising surges, improving protection margin for sensitive ICs |
| MSL Level 1 moisture sensitivity | Enables standard SMT reflow without baking, reducing manufacturing complexity and cost |
Applications
| Automotive Power Input Protection | Industrial Sensor Signal Line Clamping |
|---|---|
|
Use Scenario: Protecting 12 V power rail of automotive body control module (BCM) against ISO 7637-2 load dump and jump-start transients. IC Role / Device Role / Timing Role: Unidirectional TVS placed between battery feed and LDO input, clamping surges within 1 ns to prevent regulator latch-up or destruction. Use Value: 25.2 V clamping ensures downstream 3.3 V/5 V regulators remain below absolute maximum ratings during 100 V/500 ms load dump events. |
Use Scenario: Shielding analog output (0–5 V) of pressure sensor in factory automation PLC I/O module from ESD and inductive switching noise. IC Role / Device Role / Timing Role: TVS mounted directly at connector entry point, shunting transients before reaching op-amp buffer stage. Use Value: Sub-1 ns response and 15.3 V VWM preserve signal integrity while blocking >2 kV HBM ESD pulses per IEC 61000-4-2. |
| Telecom DC Power Feeds | Consumer Device USB Port Protection |
|
Use Scenario: Safeguarding -48 V telecom rectifier output feeding remote radio units against lightning-induced surges on outdoor cabling. IC Role / Device Role / Timing Role: Unidirectional TVS configured with cathode to -48 V rail and anode to ground, clamping negative-going transients. Use Value: 400 W PPPM rating handles multi-kA induced surges; 150 °C TJ max supports operation in sealed outdoor enclosures. |
Use Scenario: Adding secondary-level surge protection on VBUS line of USB-C port in smart home hub, supplementing primary ESD array. IC Role / Device Role / Timing Role: Standoff-rated TVS placed after USB switch, absorbing residual energy missed by front-end polymer TVS. Use Value: 15.3 V VWM avoids interference with 5 V USB signaling; 25.2 V VC prevents damage to USB PD controller during 10/1000 µs surges. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMAJ18A-E3/5A | Same VBR/VWM/VC specs, but commercial-grade (not AEC-Q101); RθJA = 135 °C/W vs. 120 °C/W | Lacks automotive qualification; suitable for industrial/commercial power supplies only | Select when AEC-Q101 is not required and higher thermal resistance is acceptable |
| 1.5SMC18A | Higher package thermal mass (SMC/DO-214AB); 1.5 kW PPPM rating but larger footprint (7.11 mm × 6.22 mm) | Better power handling but incompatible with space-constrained SMA layouts | Choose only if board area allows larger SMC package and >400 W surge margin is critical |
Compared with SMAJ18A-E3/5A and 1.5SMC18A, the P4SMA18AHM3_A/I uniquely combines AEC-Q101 qualification, halogen-free construction, and optimized thermal resistance in the compact SMA footprint - making it the preferred choice for automotive and high-reliability industrial designs requiring drop-in manufacturability and long-term supply stability.
Availability
P4SMA18AHM3_A/I is available at Aetrix Electronics and suitable for automotive electronic control units, industrial sensor interfaces, and telecom DC power feeds requiring stable component supply, long lifecycle support, and traceable halogen-free sourcing.
Supply support for P4SMA18AHM3_A/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, MOSFETs, and protection devices with emphasis on reliability, efficiency, and application-specific optimization.
The P4SMA Series is designed for high-reliability transient suppression in automotive, industrial, and telecom systems - delivering consistent clamping performance, AEC-Q101 validation, and scalable packaging across voltage grades.
FAQ
What is the breakdown voltage tolerance for P4SMA18AHM3_A/I?
The P4SMA18AHM3_A/I has a specified breakdown voltage range of 17.1 V to 18.9 V at test current IT = 1 mA, representing ±5.6 % tolerance around the nominal 18 V rating. This tight VBR window ensures predictable turn-on behavior across production lots and temperature extremes, critical for protecting voltage-sensitive loads in automotive and industrial applications. The P4SMA18AHM3_A/I maintains this specification under all conditions defined in the Vishay datasheet 88367.
Is P4SMA18AHM3_A/I suitable for bidirectional transient protection?
No, the P4SMA18AHM3_A/I is a unidirectional TVS diode, indicated by the "A" suffix and cathode band marking. It protects against positive-going transients on a line referenced to ground. For bidirectional protection (e.g., AC lines or differential signals), a "CA" suffix part like P4SMA18CA must be used. Using P4SMA18AHM3_A/I in bidirectional configurations risks forward conduction and failure during negative excursions. Always verify polarity alignment before placing P4SMA18AHM3_A/I in circuit.
What does the "HM3_A/I" suffix mean in P4SMA18AHM3_A/I?
The "HM3" denotes halogen-free, RoHS-compliant construction with whisker-resistant matte tin plating; "A" indicates unidirectional configuration and AEC-Q101 qualification; "I" specifies 7500-unit tape-and-reel packaging on 13-inch reels. This full suffix confirms the P4SMA18AHM3_A/I meets automotive reliability standards, environmental compliance requirements, and high-volume SMT assembly needs - distinguishing it from commercial-grade variants like P4SMA18A-E3/61.
How does P4SMA18AHM3_A/I perform under elevated ambient temperatures?
The P4SMA18AHM3_A/I derates linearly above TA = 25 °C per Figure 2 in datasheet 88367: at 85 °C ambient, its 400 W peak pulse power drops to ~280 W, and IPPM reduces proportionally. Its RθJA = 120 °C/W assumes minimum recommended pad layout (0.2" × 0.2" copper). To maintain performance in hot environments, use enhanced copper pour or thermal vias. The P4SMA18AHM3_A/I remains fully functional up to +150 °C junction temperature.
Can P4SMA18AHM3_A/I replace older P4SMA18A variants in existing designs?
Yes - the P4SMA18AHM3_A/I is a direct replacement for legacy P4SMA18A parts in terms of electrical specs, pinout, and footprint. It adds AEC-Q101 qualification, halogen-free materials, and improved whisker resistance, with identical VBR, VWM, VC, and thermal characteristics. No PCB or schematic changes are needed. However, confirm that the "HM3_A/I" packaging matches your assembly line's reel-handling capability before migration. The P4SMA18AHM3_A/I retains full backward compatibility while upgrading reliability and compliance.
P4SMA18AHM3_A/I Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Vishay General Semiconductor - Diodes Division
- Package/Case:
- DO-214AC, SMA
- Series:
- P4SMA, TransZorb®
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 15.3V
- Voltage - Breakdown (Min):
- 17.1V
- Voltage - Clamping (Max) @ Ipp:
- 25.2V
- Current - Peak Pulse (10/1000µs):
- 15.9A
- Power - Peak Pulse:
- 400W
- Power Line Protection:
- No
- Applications:
- Telecom
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -65°C ~ 150°C (TJ)
- Grade:
- Automotive
- Qualification:
- AEC-Q101
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- DO-214AC (SMA)
P4SMA18AHM3_A/I FAQ
1.How can I place an order for P4SMA18AHM3_A/I through Aetrix?
Please submit a Request for Quotation (RFQ) for P4SMA18AHM3_A/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 P4SMA18AHM3_A/I reliable?
The price and inventory of P4SMA18AHM3_A/I are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for P4SMA18AHM3_A/I is usually 5 days.
3.What payment methods are accepted for P4SMA18AHM3_A/I?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for P4SMA18AHM3_A/I transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for P4SMA18AHM3_A/I?
P4SMA18AHM3_A/I orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your P4SMA18AHM3_A/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 P4SMA18AHM3_A/I?
For technical support, including P4SMA18AHM3_A/I datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your P4SMA18AHM3_A/I requirements.
6.How does Aetrix verify that P4SMA18AHM3_A/I is sourced from the original manufacturer or authorized distributors?
All P4SMA18AHM3_A/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 P4SMA18AHM3_A/I meets industry standards.
7.What is the process for return or replacement of P4SMA18AHM3_A/I?
All P4SMA18AHM3_A/I units undergo pre-shipment inspection (PSI). If there is an issue with P4SMA18AHM3_A/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 P4SMA18AHM3_A/I part is unused and in its original packaging.
Return procedure for P4SMA18AHM3_A/I:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
P4SMA18AHM3_A/I Tags
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