Vishay General Semiconductor - Diodes Division P4SMA30AHM3_A/H

Overview

P4SMA30AHM3_A/H from Vishay General Semiconductor is a unidirectional surface-mount Transient Voltage Suppressor (TVS) diode in SMA (DO-214AC) package, designed for clamping voltage transients on power and signal lines. It features a 30 V standoff voltage (V_WM), 33.3 V minimum breakdown voltage (V_BR), 41.4 V maximum clamping voltage at 9.7 A peak pulse current, 400 W peak pulse power (10/1000 µs), and AEC-Q101 qualification for automotive use.

For engineers reviewing the P4SMA30AHM3_A/H datasheet, P4SMA30AHM3_A/H pinout, P4SMA30AHM3_A/H application, or P4SMA30AHM3_A/H equivalent, this device is selected for robust overvoltage protection in automotive ECUs, industrial sensor interfaces, and DC power rails where low clamping voltage, fast response (<1 ns), and halogen-free RoHS compliance are critical design requirements.

Technical Context

The P4SMA30AHM3_A/H operates as a unidirectional avalanche diode, conducting only when reverse voltage exceeds its breakdown threshold to divert surge energy to ground. Its glass-passivated junction ensures stable leakage performance and long-term reliability under repetitive transient stress.

Rated for 150 °C maximum junction temperature and MSL Level 1 moisture sensitivity, it supports lead-free reflow up to 260 °C peak. The device delivers 400 W peak pulse power with 10/1000 µs waveform on 5.0 mm × 5.0 mm copper pads, derating linearly above 25 °C ambient per published thermal curves.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), surface-mount, halogen-free, RoHS-compliant, matte tin-plated leads. Cathode indicated by band; anode is unmarked end.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar transient suppression applications.

Compared with SMAJ30AHE3_A/H, P4SMA30AHM3_A/H provides identical electrical protection with halogen-free construction; versus 1.5SMC33A, it offers tighter clamping and smaller SMA footprint-critical for dense automotive PCB layouts where space and thermal management are constrained.

Availability

P4SMA30AHM3_A/H is available at Aetrix Electronics and suitable for automotive electronic control units, industrial sensor interfaces, and 12 V/24 V DC power rail protection requiring stable component supply, AEC-Q101 validation, and halogen-free compliance.

Supply support for P4SMA30AHM3_A/H 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 targets cost-sensitive, high-volume transient suppression needs in automotive, industrial, and consumer systems-designed for robustness under harsh electrical environments and compatibility with automated SMT assembly.

FAQ

What is the maximum clamping voltage of the P4SMA30AHM3_A/H under a 10/1000 µs surge?

The P4SMA30AHM3_A/H has a maximum clamping voltage (V_C) of 41.4 V at 9.7 A peak pulse current (I_PPM) under the standardized 10/1000 µs waveform. This value is measured with the device mounted on 0.2" × 0.2" copper pads per JEDEC standards and represents the highest voltage the protected circuit will experience during such a transient event. The P4SMA30AHM3_A/H maintains this clamping performance across its qualified temperature range and lifetime.

Is the P4SMA30AHM3_A/H suitable for automotive applications?

Yes, the P4SMA30AHM3_A/H is AEC-Q101 qualified and specifically intended for automotive use. Its HM3 suffix denotes halogen-free, RoHS-compliant construction and full qualification to AEC-Q101 stress tests-including high-temperature operating life, temperature cycling, and unbiased highly accelerated stress testing. The P4SMA30AHM3_A/H is deployed in body control modules, infotainment power supplies, and sensor interfaces where reliability under vibration, thermal cycling, and electrical transients is mandatory.

What does the "HM3" suffix indicate in P4SMA30AHM3_A/H?

The "HM3" suffix in P4SMA30AHM3_A/H identifies a halogen-free, RoHS-compliant, AEC-Q101-qualified variant with JESD201 Class 2 whisker resistance. It distinguishes this version from commercial-grade E3 or M3 variants and confirms compliance with automotive material restrictions. The "_A/H" denotes revision A and 7-inch tape-and-reel packaging (1800 units per reel). The P4SMA30AHM3_A/H meets UL 497B recognition and is rated for 150 °C maximum junction temperature.

How does the P4SMA30AHM3_A/H compare to bidirectional TVS diodes like P4SMA30CA?

The P4SMA30AHM3_A/H is unidirectional and optimized for DC power line or signal line protection where polarity is fixed-e.g., 12 V supply rails or LIN bus. In contrast, P4SMA30CA is bidirectional and suited for AC-coupled or polarity-agnostic lines like USB D+/D− or RS-485. The P4SMA30AHM3_A/H offers lower leakage (<1 µA at 25.6 V) and tighter clamping than its bidirectional counterpart, but cannot suppress positive-going transients on grounded lines. Selection depends strictly on circuit topology and signal polarity requirements.

What is the thermal resistance of the P4SMA30AHM3_A/H, and how does it affect layout design?

The P4SMA30AHM3_A/H has a typical junction-to-ambient thermal resistance (R_θJA) of 120 °C/W when mounted on minimum recommended pads, and 30 °C/W junction-to-lead (R_θJL). To maintain safe operation below 150 °C junction temperature during repetitive surges, PCB layout must use at least 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal. Reducing R_θJA via additional copper pour or thermal vias directly improves surge repetition capability and long-term reliability of the P4SMA30AHM3_A/H.