Vishay General Semiconductor - Diodes Division SM6T27CAHM3_A/H

Overview

SM6T27CAHM3_A/H from Vishay General Semiconductor is a bidirectional transient voltage suppressor (TVS) diode in SMB (DO-214AA) package, designed for clamping ESD and surge transients on signal/power lines. It features a 23.1 V stand-off voltage (V_WM), 25.7–28.4 V breakdown range (V_BR), 37.5 V max clamping voltage (V_C) at 16.0 A IPPM, 600 W peak pulse power (10/1000 μs), and AEC-Q101 qualification for automotive sensor protection.

For engineers reviewing the SM6T27CAHM3_A/H datasheet, SM6T27CAHM3_A/H pinout, SM6T27CAHM3_A/H application, or SM6T27CAHM3_A/H equivalent, key selection criteria include bidirectional clamping capability, low clamping ratio (V_C/V_BR ≈ 1.39), halogen-free RoHS compliance, MSL Level 1 rating, and validated performance under IEC 61000-4-2/4-5 stress conditions.

Technical Context

This TVS operates symmetrically in both polarities due to its bidirectional construction, enabling protection of AC-coupled or differential signal paths without polarity constraints. Its glass-passivated junction ensures stable V_BR tolerance (±5%) and low leakage (<1.0 μA at V_WM), while low inductance supports fast response to sub-nanosecond transients.

The device delivers 600 W peak pulse power with a 10/1000 μs waveform when mounted on 5.0 mm × 5.0 mm copper pads, and derates linearly above T_A = 25 °C per Fig. 2. Thermal resistance R_θJA is 100 °C/W, limiting continuous power dissipation to 5.0 W at T_A = 50 °C on infinite heatsink.

Key Specifications

Pinout & Package

SMB (DO-214AA) package: cathode/anode terminals are symmetrical; no polarity marking on bidirectional devices. Dimensions: 4.57 mm × 3.94 mm × 2.20 mm (L × W × H); matte tin-plated leads compliant with J-STD-002 solderability.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ24CA and 1.5KE27CA, SM6T27CAHM3_A/H offers optimal balance of 600 W surge handling, SMB SMT compatibility, AEC-Q101 qualification, and tight V_C/V_BR ratio-making it preferred for new automotive and industrial designs requiring automated manufacturing and field reliability.

Availability

SM6T27CAHM3_A/H is available at Aetrix Electronics and suitable for automotive sensor modules, industrial CAN networks, telecom DSL line cards, and consumer USB interface protection requiring stable component supply and long-term lifecycle support.

Supply support for SM6T27CAHM3_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 SM6T Series was developed to deliver high-power, low-clamp TVS protection in compact surface-mount packages for automotive, industrial, and communications systems demanding AEC-Q101 validation and consistent surge immunity.

FAQ

What is the clamping voltage of SM6T27CAHM3_A/H at its rated peak pulse current?

The SM6T27CAHM3_A/H has a maximum clamping voltage (V_C) of 37.5 V at 16.0 A peak pulse current (I_PPM) using a 10/1000 μs waveform. This value is measured under standard test conditions per JEDEC standards and reflects the upper limit of voltage seen by downstream circuitry during worst-case surge events. The SM6T27CAHM3_A/H maintains this clamping performance across its full operating temperature range (-65 °C to +150 °C).

Is SM6T27CAHM3_A/H suitable for automotive applications?

Yes, SM6T27CAHM3_A/H is AEC-Q101 qualified and manufactured with halogen-free, RoHS-compliant materials under Vishay's HM3 automotive grade. It is specifically intended for automotive use cases such as sensor protection, body control modules, and infotainment interfaces where reliability under thermal cycling, vibration, and electrical stress is critical. The SM6T27CAHM3_A/H meets MSL Level 1 and supports reflow profiles up to 260 °C peak.

How does the bidirectional design of SM6T27CAHM3_A/H affect its circuit placement?

The bidirectional design of SM6T27CAHM3_A/H eliminates polarity sensitivity, allowing it to be placed across any two points needing symmetric overvoltage protection-such as differential signal pairs (CAN_H/CAN_L), AC-coupled lines, or ungrounded power rails. Unlike unidirectional TVS diodes, SM6T27CAHM3_A/H requires no orientation check during placement, simplifying SMT assembly and reducing misplacement risk in high-volume production.

What is the standoff voltage (V_WM) of SM6T27CAHM3_A/H and why does it matter?

The standoff voltage (V_WM) of SM6T27CAHM3_A/H is 23.1 V, representing the maximum continuous reverse voltage the device can withstand without entering conduction. This parameter ensures the SM6T27CAHM3_A/H remains non-conductive during normal operation-preserving signal integrity and minimizing leakage-while still triggering reliably above this threshold during transients. It must be selected ≥10–20% above the system's maximum operating voltage.

Does SM6T27CAHM3_A/H have a defined junction capacitance value?

No specific junction capacitance (C_J) value is published for SM6T27CAHM3_A/H in the official Vishay SM6T datasheet (Doc. #88385). While typical SMB-packaged TVS diodes in this series exhibit C_J < 100 pF at zero bias, the exact figure for SM6T27CAHM3_A/H is not characterized or guaranteed. For high-speed signal lines (e.g., USB, HDMI), designers should verify layout parasitics and consider lower-capacitance alternatives if bandwidth preservation is critical.