Taiwan Semiconductor Corporation SMCJ28

Overview

SMCJ28 from Taiwan Semiconductor is a unidirectional 1500W surface-mount transient voltage suppressor (TVS) in DO-214AB (SMC) package, with 28V working stand-off voltage (VWM), 31.1–38.0V breakdown voltage (VBR), and 50.0V maximum clamping voltage (VC) at 31A peak impulse current. It protects automotive power rails and industrial I/O interfaces against ISO 7637-2 Pulse 1/2a/2b/3a/3b transients.

For engineers reviewing the SMCJ28 datasheet, SMCJ28 pinout, SMCJ28 application, or SMCJ28 equivalent, key selection criteria include clamping performance under 10/1000μs surge, junction temperature derating above 25°C, unidirectional polarity marking, and compliance with J-STD-020 Level 1 moisture sensitivity for automated reflow assembly.

Technical Context

The SMCJ28 operates as a unidirectional avalanche diode, triggered when reverse voltage exceeds its VBR range (31.1–38.0V at 1mA test current). Its glass-passivated junction enables sub-1ps response time and <1μA leakage at 28V, meeting stringent EFT immunity requirements per IEC 61000-4-4.

Thermally, it features R_θJA = 55°C/W and R_θJC = 10°C/W, supporting continuous operation up to T_J = 150°C. The DO-214AB package provides 1500W peak pulse power dissipation (t_p = 1ms) with UL 94V-0 molding compound and matte tin-plated leads compliant with J-STD-002 solderability.

Key Specifications

Pinout & Package

DO-214AB (SMC) surface-mount package with cathode band marking on one end; leads are matte tin-plated and solderable per J-STD-002. Weight: 0.210 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ28A and 1.5KE28A, the SMCJ28 delivers 2.5× higher peak power in an SMT-optimized DO-214AB package with verified ISO 7637-2 Pulse 1/2a/2b/3a/3b immunity-making it the preferred choice for new automotive and industrial designs requiring high-reliability surface-mount TVS protection.

Availability

SMCJ28 is available at Aetrix Electronics and suitable for automotive body control modules, industrial programmable logic controllers, LED street lighting drivers, and telecom power interface circuits requiring stable component supply across extended temperature ranges and high-volume production cycles.

Supply support for SMCJ28 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, specializing in TVS diodes, rectifiers, MOSFETs, and power management devices since 1979.

The SMCJ series was designed specifically for high-energy transient suppression in automotive and industrial environments, emphasizing ISO 7637-2 compliance, tight parametric tolerances, and robust SMT manufacturability in the DO-214AB package.

FAQ

What is the clamping voltage of the SMCJ28 under a standard 10/1000μs surge?

The SMCJ28 has a maximum clamping voltage (VC) of 50.0 V when subjected to a 31 A peak impulse current (IPPM), defined per the 10/1000μs waveform in Figure 5 of the datasheet. This value is measured at TA = 25°C and ensures downstream circuitry remains within safe operating limits during standardized surge events. The SMCJ28 maintains this clamping performance across its specified junction temperature range.

Is the SMCJ28 suitable for bidirectional transient protection?

No, the SMCJ28 is a unidirectional TVS diode intended for DC line protection with defined polarity. For bidirectional applications, the SMCJ28CA variant must be used-its marking code is GFF, and it exhibits symmetrical clamping in both directions. The SMCJ28 itself has a cathode band and is rated only for reverse-biased operation; forward conduction follows standard diode behavior with VF ≈ 3.5 V at 100 A.

What is the maximum steady-state power dissipation rating for the SMCJ28?

The SMCJ28 has a steady-state power dissipation (PD) rating of 5 W at TA = 25°C, as specified in the Absolute Maximum Ratings table. This value decreases with rising ambient temperature per the derating curve in Figure 2. Unlike peak pulse power (1500 W), PD reflects continuous thermal limits and is relevant for sustained overvoltage conditions-not transient suppression. The SMCJ28 is not intended for continuous power regulation.

Does the SMCJ28 meet RoHS and halogen-free requirements?

Yes, the SMCJ28 is RoHS compliant and halogen-free per IEC 61249-2-21. The device uses lead-free matte tin-plated terminals and a molding compound free of brominated flame retardants. These compliance attributes are confirmed in the Mechanical Data section of the official Taiwan Semiconductor datasheet (Version S2104) and apply to all units shipped under standard ordering codes.

What is the moisture sensitivity level (MSL) of the SMCJ28 and how does it affect assembly?

The SMCJ28 is rated MSL Level 1 per J-STD-020, meaning it has unlimited floor life and may be stored indefinitely at ≤30°C/60% RH without baking prior to reflow. This eliminates moisture-related popcorning risk during lead-free reflow profiles and simplifies SMT line logistics. The SMCJ28's Level 1 rating is enabled by its DO-214AB package construction and UL 94V-0 molding compound.