Vishay General Semiconductor - Diodes Division 1.5SMC91AHM3_A/I

Overview

1.5SMC91AHM3_A/I from Vishay General Semiconductor is a unidirectional transient voltage suppressor (TVS) diode designed for robust overvoltage protection in power and signal lines. It features a 91 V breakdown voltage (V_BR = 86.5–95.5 V at 1 mA), 77.8 V stand-off voltage (V_WM), 125 V maximum clamping voltage (V_C) at 12 A peak pulse current, and 1500 W peak pulse power capability with 10/1000 µs waveform - deployed in automotive sensor interfaces, industrial I/O modules, and DC power rail protection.

For engineers reviewing the 1.5SMC91AHM3_A/I datasheet, 1.5SMC91AHM3_A/I pinout, 1.5SMC91AHM3_A/I application, or 1.5SMC91AHM3_A/I equivalent, this part delivers AEC-Q101 qualification, halogen-free RoHS compliance, SMC (DO-214AB) surface-mount packaging, and verified clamping performance under repetitive surge conditions per IEC 61000-4-5.

Technical Context

The 1.5SMC91AHM3_A/I operates as a unidirectional avalanche diode, leveraging glass-passivated junction technology to achieve fast response time (<1 ps) and low incremental surge resistance. Its clamping action begins at V_WM = 77.8 V and limits transient voltages to ≤125 V at I_PPM = 12 A, enabling reliable protection of downstream MOSFETs and microcontrollers.

Thermally, it exhibits R_θJA = 75 °C/W and R_θJL = 15 °C/W, supporting operation from –65 °C to +150 °C. The device is rated for 200 A non-repetitive forward surge current (I_FSM, 8.3 ms half-sine) and 6.5 W steady-state power dissipation on infinite heatsink at 50 °C.

Key Specifications

Pinout & Package

Package: SMC (DO-214AB), molded plastic case with matte tin-plated leads, MSL level 1 (260 °C peak reflow), UL 94 V-0 rated compound.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ90A and 1.5KE91A, the 1.5SMC91AHM3_A/I uniquely combines AEC-Q101 qualification, halogen-free construction, and 1500 W surge capacity in the SMC footprint - making it the only option qualified for next-generation automotive and industrial SMT production requiring zero rework risk and full regulatory traceability.

Availability

1.5SMC91AHM3_A/I is available at Aetrix Electronics and suitable for automotive sensor modules, industrial programmable logic controllers, and telecom power interface designs requiring stable component supply, long-term lifecycle assurance, and AEC-Q101 compliance.

Supply support for 1.5SMC91AHM3_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 high-reliability diodes, MOSFETs, and passive components for automotive, industrial, and computing markets.

The 1.5SMC Series was engineered specifically for surface-mount transient suppression in harsh environments, emphasizing AEC-Q101 qualification, repeatable clamping performance, and compatibility with automated SMT assembly processes.

FAQ

What is the maximum clamping voltage of the 1.5SMC91AHM3_A/I under standard test conditions?

The 1.5SMC91AHM3_A/I has a maximum clamping voltage (V_C) of 125 V when subjected to a 10/1000 µs waveform at I_PPM = 12 A. This value is measured per JEDEC standards and ensures protected circuitry remains below critical voltage thresholds during surge events. The 1.5SMC91AHM3_A/I maintains this clamping performance across its full operating temperature range (–65 °C to +150 °C).

Is the 1.5SMC91AHM3_A/I qualified for automotive applications?

Yes, the 1.5SMC91AHM3_A/I is AEC-Q101 qualified, as indicated by the "HM3" and "_A" suffixes in its ordering code. It meets stress test requirements for temperature cycling, humidity bias, and mechanical shock applicable to automotive electronics. The 1.5SMC91AHM3_A/I is commonly used in engine control units, body electronics, and ADAS sensor modules where reliability under vibration and thermal cycling is mandatory.

What does the "HM3_A/I" suffix mean in 1.5SMC91AHM3_A/I?

The "HM3" denotes halogen-free, RoHS-compliant construction with JESD201 Class 2 whisker resistance; "_A" specifies AEC-Q101 qualification for the 6.8 V to 220 V voltage range; "/I" indicates packaging in 13-inch tape-and-reel format (3500 units per reel). This full suffix confirms the 1.5SMC91AHM3_A/I meets automotive-grade material, reliability, and logistics requirements simultaneously.

How does the 1.5SMC91AHM3_A/I compare to bidirectional TVS diodes like 1.5SMC91CHM3_A/I?

The 1.5SMC91AHM3_A/I is unidirectional and intended for DC-biased lines where polarity is fixed (e.g., V_CC–GND rails); the 1.5SMC91CHM3_A/I is bidirectional and suited for AC or floating signal lines (e.g., data buses). They share identical V_BR, V_C, and P_PPM, but the 1.5SMC91AHM3_A/I exhibits lower leakage (<1 µA at V_WM) and supports higher I_FSM (200 A vs. 100 A for bidirectional variants).

What is the thermal resistance of the 1.5SMC91AHM3_A/I, and how does it affect layout design?

The 1.5SMC91AHM3_A/I has R_θJA = 75 °C/W (junction-to-ambient) and R_θJL = 15 °C/W (junction-to-leads), measured on 8.0 mm × 8.0 mm copper pads per terminal. To maintain T_J ≤ 150 °C under 6.5 W steady-state dissipation, PCB layout must provide ≥1000 mm² total copper area per pad and minimize trace length to ground planes. The 1.5SMC91AHM3_A/I's low R_θJL makes thermal coupling to internal ground planes highly effective.