Vishay General Semiconductor - Diodes Division SM6T24CA-M3/52

Overview

SM6T24CA-M3/52 from Vishay General Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in SMB (DO-214AA) package, rated for 600 W peak pulse power (10/1000 μs), 24 V standoff voltage (V_WM), and clamping voltage of 33.2 V at 18 A peak pulse current. It protects signal lines and power rails in automotive sensor units and industrial control interfaces against ESD and inductive switching transients.

For engineers reviewing the SM6T24CA-M3/52 datasheet, SM6T24CA-M3/52 pinout, SM6T24CA-M3/52 application, or SM6T24CA-M3/52 equivalent, key selection criteria include bidirectional clamping capability, halogen-free RoHS compliance (M3 suffix), AEC-Q101 qualification eligibility, low-inductance SMB package layout, and thermal resistance of 100 °C/W junction-to-ambient.

Technical Context

This bidirectional TVS operates symmetrically across both polarities with identical breakdown (V_BR = 22.8–25.2 V at 1 mA) and clamping (V_C = 33.2 V at 18 A) characteristics in either direction. Its glass-passivated junction ensures stable leakage (<1 μA at 20.5 V) and robust surge handling under repetitive transient stress.

The device is optimized for surface-mount automated placement on PCBs with 0.2" × 0.2" copper pads per terminal, delivering 600 W pulse power while maintaining low parasitic inductance and meeting J-STD-020 MSL Level 1 (260 °C peak reflow).

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), surface-mount, halogen-free, RoHS-compliant, matte tin-plated leads solderable per J-STD-002. No polarity marking - bidirectional symmetry eliminates cathode/anode orientation concerns during placement.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ24CA and SMCJ24CA, the SM6T24CA-M3/52 delivers optimal balance of 600 W surge capability, SMB footprint compatibility, and halogen-free manufacturability-making it the preferred choice for cost-sensitive, space-constrained automotive and industrial designs requiring AEC-Q101 readiness.

Availability

SM6T24CA-M3/52 is available at Aetrix Electronics and suitable for automotive sensor modules, industrial PLC I/O cards, consumer power adapter front-ends, and telecom line card protection requiring stable component supply and halogen-free compliance.

Supply support for SM6T24CA-M3/52 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, MOSFETs, optoelectronics, and passive components with emphasis on reliability and application-specific performance.

The SM6T Series is designed specifically for robust transient suppression in harsh environments-including automotive under-hood, industrial automation, and telecom infrastructure-where bidirectional clamping, high surge tolerance, and AEC-Q101 qualification are mandatory.

FAQ

What is the clamping voltage of the SM6T24CA-M3/52 at its rated peak pulse current?

The SM6T24CA-M3/52 has a maximum clamping voltage (V_C) of 33.2 V at 18 A peak pulse current with a 10/1000 μs waveform. This value is measured under standardized test conditions per JEDEC and ensures predictable overvoltage limiting for downstream circuitry. The SM6T24CA-M3/52 maintains this clamping performance bidirectionally, making it suitable for protecting AC-coupled or differential signal paths where polarity reversal may occur.

Is the SM6T24CA-M3/52 qualified for automotive applications?

The SM6T24CA-M3/52 is halogen-free and RoHS-compliant, and belongs to the AEC-Q101-qualified SM6T family. While the base part number SM6T24CA-M3/52 itself carries the M3 suffix indicating halogen-free commercial grade, AEC-Q101 qualification is achieved with ordering codes ending in HM3_X (e.g., SM6T24CAHM3_A). Therefore, the SM6T24CA-M3/52 can be used in automotive designs when paired with appropriate qualification documentation and process controls.

What does the "CA" suffix indicate in SM6T24CA-M3/52?

The "CA" suffix in SM6T24CA-M3/52 explicitly denotes a bidirectional configuration - meaning the device provides symmetrical transient suppression in both forward and reverse directions. Unlike unidirectional variants (e.g., SM6T24A), the SM6T24CA-M3/52 has no polarity marking and functions identically regardless of voltage polarity across its terminals, simplifying layout and enabling use in AC signal paths or differential bus protection.

What is the thermal resistance of the SM6T24CA-M3/52, and how does it affect layout?

The SM6T24CA-M3/52 has a typical junction-to-ambient thermal resistance (R_θJA) of 100 °C/W when mounted on 0.2" × 0.2" copper pads per terminal. This value directly determines allowable power dissipation at elevated ambient temperatures - for example, at 75 °C ambient, derated power drops to ~2.5 W. Layout must follow Vishay's recommended pad dimensions (minimum 0.060" × 0.086") to achieve this R_θJA; reducing copper area increases thermal resistance and risks premature thermal runaway during repetitive surges.

How does the SM6T24CA-M3/52 compare to unidirectional TVS diodes in circuit implementation?

The SM6T24CA-M3/52 eliminates the need for polarity-aware placement and enables single-component protection of bidirectional signals such as RS-485, CAN, or audio lines - unlike unidirectional SM6T24A, which requires correct cathode orientation relative to ground. Its symmetrical V_BR and V_C ensure identical clamping behavior regardless of transient polarity, reducing BOM count and assembly errors. The SM6T24CA-M3/52 also avoids potential misapplication in AC-coupled circuits where reverse voltage could forward-bias a unidirectional device.