Vishay General Semiconductor - Diodes Division SM6T24CAHE3/52

Overview

SM6T24CAHE3/52 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 24 V standoff voltage (VWM), 33.2 V max clamping voltage at 18 A IPPM, 600 W peak pulse power (10/1000 μs), and AEC-Q101 qualification for automotive electronics protection.

For engineers reviewing the SM6T24CAHE3/52 datasheet, SM6T24CAHE3/52 pinout, SM6T24CAHE3/52 application, or SM6T24CAHE3/52 equivalent, key selection criteria include bidirectional clamping capability, low clamping ratio (1.38×VWM), RoHS-compliant AEC-Q101 qualification, SMB thermal performance (RθJA = 100 °C/W), and compatibility with automated SMT placement on 5.0 mm × 5.0 mm copper pads.

Technical Context

This bidirectional TVS operates symmetrically across both polarities, with breakdown voltage VBR of 26.7–29.5 V at 1 mA test current and guaranteed clamping under 10/1000 μs surge waveforms. Its glass-passivated junction ensures stable leakage (<1 μA at 20.5 V) and robust surge handling up to 100 A IFSM (unidirectional only, not applicable here).

The device meets J-STD-020 MSL Level 1 (260 °C peak reflow), uses matte tin-plated leads, and is rated for -65 °C to +150 °C junction temperature. Thermal resistance RθJL = 20 °C/W supports localized heat dissipation in compact PCB layouts without heatsinking.

Key Specifications

Pinout & Package

SMB (DO-214AA) package: molded plastic case with matte tin-plated leads, UL 94 V-0 rated compound, 0.205" × 0.220" body outline, and no polarity marking for bidirectional configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ24CA and 1.5KE24CA, SM6T24CAHE3/52 delivers superior surge robustness in an AEC-Q101-qualified SMT package, enabling automotive-grade reliability without sacrificing assembly efficiency or thermal performance.

Availability

SM6T24CAHE3/52 is available at Aetrix Electronics and suitable for automotive sensor interfaces, industrial CAN bus nodes, consumer USB ports, and telecom DSL line protection requiring stable component supply and AEC-Q101 compliance.

Supply support for SM6T24CAHE3/52 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, rectifiers, MOSFETs, and protection devices with emphasis on reliability and application-specific performance.

The SM6T Series is engineered for high-reliability transient suppression in automotive, industrial, and communications systems, combining AEC-Q101 qualification, 600 W surge capability, and standardized SMB packaging for seamless integration.

FAQ

What is the clamping voltage of SM6T24CAHE3/52 under a 10/1000 μs surge?

The SM6T24CAHE3/52 has a maximum clamping voltage (VC) of 33.2 V at 18 A peak pulse current with a 10/1000 μs waveform. This value is measured per Figure 1 in the Vishay datasheet 88385 and reflects worst-case performance under standardized surge conditions. The clamping behavior remains symmetrical in both directions due to its bidirectional design, making SM6T24CAHE3/52 suitable for protecting balanced or floating signal paths.

Is SM6T24CAHE3/52 qualified for automotive applications?

Yes, SM6T24CAHE3/52 is AEC-Q101 qualified, as confirmed by the "HE3" suffix in its ordering code and documentation in Vishay's SM6T series datasheet (Rev. 09-Jan-2024). This qualification covers stress testing for temperature cycling, humidity, mechanical shock, and surge robustness required for automotive electronic control units. SM6T24CAHE3/52 is intended for use in engine compartments, body electronics, and ADAS sensor interfaces where reliability under harsh conditions is mandatory.

What does the "CA" suffix indicate in SM6T24CAHE3/52?

The "CA" suffix in SM6T24CAHE3/52 denotes a bidirectional configuration, meaning the device provides symmetrical transient suppression for both positive and negative voltage excursions. Unlike unidirectional variants (e.g., SM6T24A), SM6T24CAHE3/52 has no cathode marking and functions identically regardless of polarity applied across its terminals. This makes SM6T24CAHE3/52 ideal for AC-coupled lines, differential buses like CAN or RS-485, and other applications where voltage transients may swing above or below ground.

What is the thermal resistance of SM6T24CAHE3/52, and how does it affect PCB layout?

SM6T24CAHE3/52 has a typical junction-to-ambient thermal resistance (RθJA) of 100 °C/W when mounted on 0.2" × 0.2" (5.0 mm × 5.0 mm) copper pads per terminal, and junction-to-lead resistance (RθJL) of 20 °C/W. These values require adherence to Vishay's recommended pad layout to maintain safe junction temperatures under repeated surge events. Deviating from the specified copper area increases thermal impedance, risking premature failure during sustained transient activity-especially critical in automotive or industrial deployments where SM6T24CAHE3/52 may experience multiple surges per hour.

How does SM6T24CAHE3/52 compare to unidirectional TVS diodes in circuit design?

SM6T24CAHE3/52 eliminates polarity sensitivity, allowing placement without regard to signal direction-unlike unidirectional TVS diodes such as SM6T24A, which require correct cathode orientation relative to the protected rail. This simplifies layout, reduces BOM count in mixed-signal systems, and avoids field failures from reversed installation. However, SM6T24CAHE3/52 exhibits slightly higher leakage than unidirectional equivalents at the same VWM, though still limited to <1 μA, making it fully compatible with low-power sensor and communication interfaces.