Vishay General Semiconductor - Diodes Division 1.5SMC33AHE3_A/H

Overview

1.5SMC33AHE3_A/H 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 33 V breakdown voltage (V_BR = 31.4–34.7 V at 1 mA), 28.2 V stand-off voltage (V_WM), clamps to ≤45.7 V at 32.8 A peak pulse current, and delivers 1500 W peak pulse power with a 10/1000 μs waveform - used to safeguard MOSFETs, ICs, and sensor interfaces in automotive and industrial power supplies.

For engineers reviewing the 1.5SMC33AHE3_A/H datasheet, 1.5SMC33AHE3_A/H pinout, 1.5SMC33AHE3_A/H application, or 1.5SMC33AHE3_A/H equivalent, this device is selected for high-reliability unidirectional surge suppression where AEC-Q101 qualification, low incremental surge resistance, and fast response time (<1 ns) are critical in 12 V–24 V DC systems.

Technical Context

The 1.5SMC33AHE3_A/H operates as a unidirectional clamping device with a glass-passivated junction and cathode-band polarity marking. Its thermal resistance is R_θJA = 75 °C/W (on recommended 8.0 mm × 8.0 mm copper pads) and R_θJL = 15 °C/W, enabling effective heat dissipation during repetitive transients up to 0.01% duty cycle.

It meets J-STD-020 MSL Level 1 (peak reflow ≤260 °C), supports 200 A non-repetitive forward surge (8.3 ms half-sine), and exhibits a V_BR temperature coefficient of +0.098 %/°C - ensuring stable clamping behavior across its -65 °C to +150 °C operating junction range.

Key Specifications

Pinout & Package

Package: SMC (DO-214AB), surface-mount, low-profile case with matte tin-plated leads solderable per J-STD-002 and JESD 22-B102. Cathode identified by black band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ33A-E3/52 and 1.5KE33A, the 1.5SMC33AHE3_A/H uniquely combines AEC-Q101 qualification, 1500 W surge capacity, and SMC surface-mount compatibility - making it the only option among the three validated for high-volume automotive SMT production with full load-dump immunity.

Availability

1.5SMC33AHE3_A/H is available at Aetrix Electronics and suitable for automotive power modules, industrial sensor nodes, DC motor controllers, and telecom power supplies requiring stable component supply, AEC-Q101 compliance, and repeatable surge performance.

Supply support for 1.5SMC33AHE3_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, power handling, and automotive qualification.

The 1.5SMC Series was developed for high-energy transient suppression in space-constrained SMT applications - targeting automotive, industrial, and telecom systems needing robust, AEC-Q101-compliant unidirectional TVS diodes in the SMC package.

FAQ

What is the clamping voltage of the 1.5SMC33AHE3_A/H under maximum rated surge current?

The 1.5SMC33AHE3_A/H clamps to a maximum of 45.7 V when subjected to its rated peak pulse current of 32.8 A (10/1000 μs waveform). This value is measured per standard test conditions and ensures downstream components see limited overvoltage stress during transient events. The 1.5SMC33AHE3_A/H maintains this clamping performance across its full operating temperature range and after repeated surges within its specified duty cycle.

Is the 1.5SMC33AHE3_A/H qualified for automotive applications?

Yes, the 1.5SMC33AHE3_A/H is AEC-Q101 qualified, as confirmed by Vishay's documentation and ordering code suffix "HE3". This qualification covers stress tests including high-temperature reverse bias (HTRB), high-temperature gate bias (HTGB), temperature cycling (TCT), and unbiased highly accelerated stress testing (UHAST), validating its suitability for under-hood and powertrain applications. The 1.5SMC33AHE3_A/H meets automotive reliability requirements without derating.

What does the "_A/H" suffix in 1.5SMC33AHE3_A/H indicate?

The "_A/H" suffix in 1.5SMC33AHE3_A/H specifies the packaging configuration: "A" denotes the revision level (per Vishay's revision coding), and "H" indicates 7-inch plastic tape-and-reel delivery with 850 units per reel. This format aligns with Vishay's standard ordering nomenclature for AEC-Q101-qualified SMC devices and ensures compatibility with high-speed pick-and-place equipment. The 1.5SMC33AHE3_A/H is RoHS-compliant and halogen-free.

How does the 1.5SMC33AHE3_A/H compare to bidirectional TVS diodes in the same series?

The 1.5SMC33AHE3_A/H is unidirectional and intended for DC line protection where polarity is fixed - unlike bidirectional variants (e.g., 1.5SMC33CA) that protect AC or floating signals. Its cathode band marks polarity, and it conducts only during reverse-bias transients. Bidirectional types lack polarity marking and clamp symmetrically, but exhibit higher leakage above V_WM. For 12 V automotive rails, the 1.5SMC33AHE3_A/H offers tighter leakage control and optimized clamping for known-polarity surges.

What is the thermal resistance of the 1.5SMC33AHE3_A/H, and how does it affect layout design?

The 1.5SMC33AHE3_A/H has a typical junction-to-ambient thermal resistance (R_θJA) of 75 °C/W when mounted on 8.0 mm × 8.0 mm copper pads per terminal - a requirement explicitly defined in Vishay's datasheet. To achieve this rating, PCB layout must replicate those pad dimensions and ensure adequate copper area and thermal vias. Failure to meet this layout results in higher junction temperatures, reduced surge endurance, and potential premature failure during repetitive transients. The 1.5SMC33AHE3_A/H also has R_θJL = 15 °C/W for lead-to-case conduction.