Taiwan Semiconductor Corporation SMCJ64

Overview

SMCJ64 from Taiwan Semiconductor is a unidirectional 1500W surface-mount transient voltage suppressor (TVS) diode in DO-214AB (SMC) package, with 64V working stand-off voltage (VWM), 71.1–86.9V breakdown voltage (VBR), and 114V maximum clamping voltage (VC) at 13.8A peak pulse current-designed for automotive load-dump and inductive switching protection in power supply rails.

For engineers reviewing the SMCJ64 datasheet, SMCJ64 pinout, SMCJ64 application, or SMCJ64 equivalent, key selection criteria include clamping performance under ISO 7637-2 Pulse 5a, thermal derating above 25°C ambient, unidirectional polarity marking, and compatibility with automated SMT placement on high-reliability industrial PCBs.

Technical Context

The SMCJ64 operates as a unidirectional avalanche diode, triggered when reverse voltage exceeds its VBR range (71.1–86.9V at 1mA test current); it clamps transients to ≤114V within <1.0ps response time, limiting energy dissipation via its 1500W peak pulse rating (tp = 1ms, 10/1000μs waveform). Its glass-passivated junction ensures stable breakdown and low leakage (<1μA at 64V).

Thermally, the device features R_θJA = 55°C/W and R_θJC = 10°C/W, enabling operation up to +150°C junction temperature; its DO-214AB package supports 200A non-repetitive forward surge (IFSM) and meets JESD201 Class 2 whisker resistance and UL 94V-0 flammability standards.

Key Specifications

Pinout & Package

DO-214AB (SMC) package: molded plastic case with matte tin-plated leads, cathode band marking for unidirectional polarity, JEDEC-compliant footprint, and 0.210 g typical weight. Complies with J-STD-020 moisture sensitivity level 1 (unlimited floor life at ≤30°C/60% RH).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ64A and 1.5KE68A, the SMCJ64 delivers 2.5× higher peak power handling in a surface-mount package with sub-picosecond response and <1μA leakage-making it the preferred choice for automotive-grade, high-reliability SMT transient suppression where board area, thermal margin, and clamping speed are critical.

Availability

SMCJ64 is available at Aetrix Electronics and suitable for automotive electronics, industrial PLCs, LED lighting systems, and telecom power interfaces requiring stable component supply, consistent parametric performance, and full traceability across production lots.

Supply support for SMCJ64 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 belongs to TSC's high-power transient suppression product line, engineered specifically for automotive and industrial applications demanding robust ISO 7637-2 compliance, low clamping ratio, and extended temperature operation.

FAQ

What is the clamping voltage of the SMCJ64 under standard 10/1000μs surge conditions?

The SMCJ64 has a maximum clamping voltage (VC) of 114 V when subjected to a 13.8 A peak pulse current with a 10/1000μs waveform. This value is measured per ANSI/IEEE C62.35 and defines the upper voltage limit imposed on protected circuitry during worst-case transient events-critical for verifying compatibility with downstream IC voltage ratings.

Is the SMCJ64 unidirectional or bidirectional, and how is polarity identified?

The SMCJ64 is a unidirectional TVS diode, indicated by the absence of "C" or "CA" suffix. Polarity is marked by a cathode band on the DO-214AB package body; the banded end connects to the protected line (e.g., 12V rail), while the unmarked end connects to ground. Bidirectional variants require explicit "C" suffix (e.g., SMCJ64C).

Does the SMCJ64 meet automotive transient immunity standards such as ISO 7637-2?

Yes, the SMCJ64 is explicitly rated to meet ISO 7637-2 for Pulses 1, 2a, 2b, 3a, 3b, and 5a. Its 1500W peak power rating, fast <1.0ps response, and controlled clamping behavior enable compliance with load-dump (Pulse 5a) and inductive switching (Pulse 1) requirements common in 12V/24V automotive systems.

What is the maximum junction temperature and thermal resistance of the SMCJ64?

The SMCJ64 has a maximum junction temperature (TJ) of +150°C and thermal resistances of R_θJA = 55°C/W (junction-to-ambient) and R_θJC = 10°C/W (junction-to-case). These values allow accurate thermal modeling in PCB layouts with defined copper area and airflow, supporting reliable operation in under-hood or enclosed industrial enclosures.

How does the SMCJ64 differ from the SMCJ64A variant?

The SMCJ64A offers tighter breakdown voltage tolerance (71.1–78.6V vs. 71.1–86.9V for SMCJ64) and lower clamping voltage (103V vs. 114V at rated IPPM), resulting in improved protection margin for sensitive downstream components. Both share identical package, power rating, and application scope-but SMCJ64A is preferred where precise clamping control is prioritized over cost or availability.