Vishay General Semiconductor - Diodes Division P4SMA22AHM3_A/H

Overview

P4SMA22AHM3_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 22 V breakdown voltage (V_BR = 20.9–23.1 V at 1 mA), 18.8 V standoff voltage (V_WM), 30.6 V clamping voltage (V_C) at 13.1 A peak pulse current, and 400 W peak pulse power capability with 10/1000 µs waveform - used to protect MOSFETs, ICs, and sensor interfaces in automotive and industrial power rails.

For engineers reviewing the P4SMA22AHM3_A/H datasheet, P4SMA22AHM3_A/H pinout, P4SMA22AHM3_A/H application, or P4SMA22AHM3_A/H equivalent, this device is selected for robust ESD and surge protection where AEC-Q101 qualification, low incremental surge resistance, and fast response time (<1 ns) are required in space-constrained PCB layouts.

Technical Context

The P4SMA22AHM3_A/H operates as a unidirectional avalanche diode, conducting only when reverse voltage exceeds its breakdown threshold. Its glass-passivated junction ensures stable V_BR tolerance (±5%) and low leakage (<1 µA at V_WM), while thermal resistance (R_θJA = 120 °C/W) supports operation up to 150 °C junction temperature under defined pad layout conditions.

It delivers 400 W peak pulse power per 10/1000 µs waveform at T_A = 25 °C, derating linearly above 25 °C per Fig. 2; clamping performance is validated at I_PPM = 13.1 A, with V_C = 30.6 V ensuring safe voltage limiting for downstream 3.3 V/5 V/12 V logic and power stages.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), surface-mount, low-profile plastic case with matte tin-plated leads solderable per J-STD-002; cathode indicated by band at one end.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ22A-E3/5A and 1.5SMC22A, the P4SMA22AHM3_A/H uniquely combines AEC-Q101 qualification, SMA footprint efficiency, and guaranteed 400 W surge handling - making it the preferred choice for new automotive and high-reliability industrial designs where board space and qualification are critical.

Availability

P4SMA22AHM3_A/H is available at Aetrix Electronics and suitable for automotive power rail protection, industrial sensor interface hardening, and telecom DC feeding requiring stable component supply across multi-year production cycles.

Supply support for P4SMA22AHM3_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, and protection devices with emphasis on reliability, precision, and application-specific validation.

The P4SMA Series targets high-volume, high-reliability transient suppression in automotive, industrial, and communications infrastructure - engineered for consistent clamping performance, AEC-Q101 compliance, and seamless SMT integration.

FAQ

What is the clamping voltage of the P4SMA22AHM3_A/H under a 10/1000 µs surge?

The P4SMA22AHM3_A/H has a maximum clamping voltage (V_C) of 30.6 V at 13.1 A peak pulse current under the standardized 10/1000 µs waveform. This value is measured per Figure 1 in the Vishay datasheet 88367 and ensures protected circuits remain below critical overvoltage thresholds during surge events. The P4SMA22AHM3_A/H maintains this clamping performance across its qualified temperature range and after repeated stress cycles.

Is the P4SMA22AHM3_A/H suitable for automotive applications?

Yes, the P4SMA22AHM3_A/H is AEC-Q101 qualified (indicated by the HM3 suffix), meaning it has passed rigorous stress tests including temperature cycling, high-temperature reverse bias, and ESD immunity required for automotive electronics. Its 150 °C maximum junction temperature and MSL Level 1 rating further validate its suitability for under-hood and body-control module deployments. The P4SMA22AHM3_A/H is explicitly listed in Vishay's automotive-grade ordering matrix.

What does the "HM3" suffix mean in P4SMA22AHM3_A/H?

The "HM3" suffix in P4SMA22AHM3_A/H denotes halogen-free, RoHS-compliant construction with AEC-Q101 qualification. It distinguishes this variant from commercial-grade versions (e.g., E3 or M3) and confirms compliance with automotive reliability standards, material restrictions, and assembly requirements including lead-free reflow compatibility. The "_A/H" indicates revision A in 7-inch tape-and-reel packaging (1800 pcs/reel).

How does the P4SMA22AHM3_A/H compare to bidirectional TVS diodes?

The P4SMA22AHM3_A/H is unidirectional and intended for DC line protection where polarity is fixed - such as 12 V battery inputs or −48 V telecom feeds. Unlike bidirectional variants (e.g., P4SMA22CA), it blocks forward current and clamps only in reverse, offering tighter V_WM and lower leakage. For AC or floating signal lines, a bidirectional device would be required; the P4SMA22AHM3_A/H is not interchangeable in those roles.

What is the thermal resistance of the P4SMA22AHM3_A/H, and how does it affect layout?

The P4SMA22AHM3_A/H has a typical junction-to-ambient thermal resistance (R_θJA) of 120 °C/W when mounted on minimum recommended 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal. This value assumes no additional heatsinking; exceeding 3.3 W steady-state dissipation requires careful thermal design. Layout must follow Vishay's pad dimensions in Document 88367 to ensure rated surge performance and avoid premature thermal failure. The P4SMA22AHM3_A/H relies on PCB copper for heat spreading, not internal heatsinks.