Taiwan Semiconductor Corporation SMAJ26C

Overview

SMAJ26C from Taiwan Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in DO-214AC (SMA) package, designed for robust overvoltage protection in DC power rails. It features a 26 V working stand-off voltage (V_WM), 28.9–35.3 V breakdown voltage (V_BR @ 1 mA), 46.6 V maximum clamping voltage (V_C) at 8.6 A peak pulse current, and 400 W peak pulse power rating (10/1000 µs waveform). It is commonly deployed in automotive power supplies and industrial DC/DC converters to suppress ESD and load-dump transients.

For engineers reviewing the SMAJ26C datasheet, SMAJ26C pinout, SMAJ26C application, or SMAJ26C equivalent, key selection criteria include clamping performance under ISO 7637-2 Pulse 1/2a/2b/3a/3b, junction temperature derating above 25°C, moisture sensitivity level (MSL 1), and compatibility with automated SMT placement on high-reliability PCBs.

Technical Context

The SMAJ26C operates as a unidirectional avalanche diode, conducting only when reverse voltage exceeds its specified breakdown threshold. Its glass-passivated junction ensures stable leakage (<1 µA at V_WM) and fast response (<1.0 ps from 0 V to V_{BR min}). It is rated for 150°C maximum junction temperature and supports single-pulse surge handling up to 8.6 A (10/1000 µs).

Designed for compliance with ISO 7637-2 for automotive transient immunity, the device delivers consistent clamping behavior across its operating temperature range (−55°C to +150°C) and meets JESD201 Class 2 whisker resistance and UL 94V-0 flammability requirements in its DO-214AC molded package.

Key Specifications

Pinout & Package

DO-214AC (SMA) package: surface-mount, single-diode configuration with cathode band marking. Matte tin-plated leads meet J-STD-002 solderability; polarity is marked by a band indicating cathode terminal.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ26A, the SMAJ26C offers higher clamping voltage but broader V_BR tolerance-suited for cost-sensitive designs where ±10% V_BR variation is acceptable. Against SMBJ26C, it trades surge margin for space-constrained layouts where DO-214AC footprint is mandatory.

Availability

SMAJ26C is available at Aetrix Electronics and suitable for automotive power supply protection, industrial DC/DC converter input stages, and LED driver power stage applications requiring stable component supply, full traceability, and long-lifecycle support.

Supply support for SMAJ26C 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 power management, protection, and signal conditioning devices.

The SMAJ series is part of TSC's transient voltage suppressor product line, engineered specifically for high-reliability, high-surge-capacity protection in automotive, industrial, and telecom power systems.

FAQ

What is the polarity configuration of the SMAJ26C?

The SMAJ26C is a unidirectional TVS diode, meaning it conducts only in reverse bias above its breakdown voltage. Its cathode is marked by a band on the DO-214AC body and must be connected toward the ground or low-impedance return path. This configuration ensures proper clamping during positive transients on the anode side, and it is not interchangeable with bidirectional variants like SMAJ26CA without circuit redesign.

Does the SMAJ26C meet automotive qualification standards?

Yes, the SMAJ26C meets ISO 7637-2 Pulse 1, 2a, 2b, 3a, and 3b test requirements for automotive electrical disturbances. It is also rated for operation from −55°C to +150°C junction temperature and complies with JESD201 Class 2 whisker resistance and MSL Level 1 per J-STD-020-making it suitable for under-hood and engine-control module applications where the SMAJ26C is deployed.

What is the maximum peak pulse current the SMAJ26C can handle?

The SMAJ26C is rated for a maximum peak impulse current (I_PPM) of 8.6 A under the standardized 10/1000 µs double-exponential waveform. This value corresponds directly to its 400 W peak pulse power rating at 25°C ambient. Derating applies above 25°C per Figure 2 in the official datasheet, and actual sustainable surge count depends on thermal recovery between pulses.

How does the SMAJ26C differ from the SMAJ26A variant?

The SMAJ26C has a wider breakdown voltage range (28.9–35.3 V) versus the SMAJ26A (28.9–31.9 V), resulting in a higher maximum clamping voltage (46.6 V vs. 42.1 V at rated I_PPM). Both share identical V_WM (26 V), package (DO-214AC), and P_PPM (400 W), but the SMAJ26A provides tighter V_BR control and lower clamping-making the SMAJ26C more tolerant of process variation while the SMAJ26A suits precision-clamp designs.

Is the SMAJ26C RoHS and halogen-free compliant?

Yes, the SMAJ26C is fully RoHS compliant and halogen-free per IEC 61249-2-21. Its molding compound meets UL 94V-0 flammability rating, and its matte tin-plated leads satisfy J-STD-002 solderability requirements. These certifications are confirmed in the official Taiwan Semiconductor documentation for the SMAJ26C and apply to all units shipped under standard ordering codes.