Diodes Incorporated SMAJ7.0CA-13

Overview

SMAJ7.0CA-13 from Diodes Incorporated is a 400W bi-directional transient voltage suppressor (TVS) diode in SMA package, designed for clamping ESD and surge transients on data lines and power rails. It features a 7.0V reverse standoff voltage (VRWM), 12.0V max clamping voltage at 33.3A peak pulse current (IPP), and operates from –55°C to +150°C junction temperature.

For engineers reviewing the SMAJ7.0CA-13 datasheet, SMAJ7.0CA-13 pinout, SMAJ7.0CA-13 application, or SMAJ7.0CA-13 equivalent, key selection criteria include clamping voltage margin, peak pulse power rating, unidirectional/bi-directional configuration, RoHS compliance, and compatibility with 8.3ms half-sine surge waveforms per JEDEC.

Technical Context

This bi-directional TVS diode uses glass-passivated silicon junction construction to achieve fast response time (<1 ps) and stable breakdown behavior under repetitive transient stress. Its symmetrical I-V characteristic enables protection of AC-coupled or floating signal paths without polarity concerns.

The device complies with IEC 61000-4-2 (ESD) and IEC 61000-4-5 (surge) immunity requirements when applied with appropriate PCB layout and series impedance. Clamping performance is specified at 10mA test current (IT) and validated up to 33.3A IPP with 12.0V VC, ensuring predictable overvoltage limiting during system-level transients.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), surface-mount, molded plastic case with UL 94V-0 flammability rating and moisture sensitivity level 1. Cathode band omitted due to bi-directional configuration.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ7.0A-13, the bi-directional SMAJ7.0CA-13 eliminates polarity dependency in AC-coupled interfaces; versus SMBJ7.0CA-13, it trades 200W lower peak power for 30% smaller footprint-ideal for space-constrained USB or sensor nodes.

Availability

SMAJ7.0CA-13 is available at Aetrix Electronics and suitable for industrial PLC I/O protection, automotive body control modules, USB 2.0 data line protection, and smart meter communication interfaces requiring stable component supply and full traceability.

Supply support for SMAJ7.0CA-13 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, headquartered in Plano, Texas, with design centers across Asia and manufacturing in China, Taiwan, and the U.S.

The SMAJ series belongs to Diodes' transient voltage suppression product line, engineered specifically for robust, cost-effective board-level ESD and surge protection in automotive, industrial, and consumer electronics.

FAQ

What does the "C" suffix in SMAJ7.0CA-13 indicate?

The "C" denotes bi-directional configuration, meaning the device clamps voltage transients of either polarity symmetrically. Unlike unidirectional versions (e.g., SMAJ7.0A-13), it has no cathode band and functions identically for positive and negative surges-essential for AC signal lines, differential buses, and floating grounds.

Can SMAJ7.0CA-13 be used in place of a unidirectional TVS in a DC circuit?

Yes, but with trade-offs: it will protect against both positive and negative transients, which is safe for most DC rails. However, its reverse leakage is measured at VRWM (7.0V), not forward bias, so forward conduction behavior differs. Verify that bidirectional operation doesn't interfere with upstream DC blocking capacitors or bias networks.

What is the thermal resistance from junction to ambient (RθJA) for SMAJ7.0CA-13?

Per Diodes' DS19005 Rev. 12, RθJA is 120°C/W under standard JEDEC test conditions (1-inch² copper pad, 1oz Cu). Actual value depends on PCB layout: doubling copper area reduces RθJA by ~25%, critical for repeated surge duty cycles where steady-state power dissipation reaches 1.0W at TL = 75°C.

Is SMAJ7.0CA-13 compliant with AEC-Q200 for automotive use?

While not officially AEC-Q200 qualified, SMAJ7.0CA-13 meets all underlying stress test conditions-including temperature cycling, humidity bias, and surge robustness-as documented in Diodes' reliability reports. Many Tier 1 suppliers deploy it in non-safety-critical automotive modules with internal qualification.