Diodes Incorporated SMAJ6.5CA-13

Overview

SMAJ6.5CA-13 from Diodes Incorporated is a bi-directional 400W surface-mount transient voltage suppressor (TVS) diode designed for primary overvoltage protection in DC power rails and signal lines. It features a 6.5V reverse standoff voltage (VRWM), 7.22–7.98V breakdown voltage (VBR) at 10mA, 11.2V max clamping voltage (VC) at 35.7A peak pulse current (IPP), and operates from –55°C to +150°C.

For engineers reviewing the SMAJ6.5CA-13 datasheet, SMAJ6.5CA-13 pinout, SMAJ6.5CA-13 application, or SMAJ6.5CA-13 equivalent, key selection criteria include clamping performance under 8.3ms surge, unidirectional/bi-directional polarity configuration, RoHS-compliant lead-free plating, and compatibility with automated SMT assembly on PCBs requiring IEC 61000-4-2/4-4/4-5 level protection.

Technical Context

This bi-directional TVS diode uses glass-passivated silicon junction construction to achieve fast response time (<1ps) and stable clamping during ESD and lightning-induced transients. Its symmetrical I-V characteristic enables protection of AC-coupled or floating signal paths without polarity constraints.

The device complies with JEDEC-standard 8.3ms half-sine surge testing (IFSM = 40A), supports steady-state power dissipation of 1.0W at TL = 75°C, and maintains low leakage (<500nA at VRWM) to avoid loading sensitive analog or communication circuits.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), molded plastic case with UL 94V-0 flammability rating, cathode band omitted (bi-directional configuration).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ6.5A-13, the bi-directional variant eliminates polarity dependency for AC or floating nodes; versus SMBJ6.5CA-13, it trades 200W peak power headroom for 30% smaller PCB footprint and identical clamping performance at rated 400W.

Availability

SMAJ6.5CA-13 is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial programmable logic controllers, smart energy metering hardware, and USB-C peripheral designs requiring stable component supply across production lifecycles.

Supply support for SMAJ6.5CA-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 and manufacturing operations across Asia and the Americas.

The SMAJ series belongs to Diodes' transient voltage suppression portfolio, engineered specifically for high-reliability board-level surge and ESD protection in automotive, industrial, and communications equipment.

FAQ

What does the "C" suffix in SMAJ6.5CA-13 indicate?

The "C" denotes bi-directional configuration: the device has symmetrical clamping behavior in both polarities, with no cathode band marking. This enables protection of AC signals, differential buses, or floating power domains without regard to voltage polarity-unlike unidirectional variants (e.g., SMAJ6.5A-13) that conduct only in reverse bias.

Can SMAJ6.5CA-13 be used in place of a unidirectional TVS in a DC circuit?

Yes, but with trade-offs: bi-directional operation introduces forward conduction during positive transients, potentially increasing leakage current and power dissipation. For pure DC rails with known polarity, unidirectional devices offer lower standby leakage (<100nA vs. <500nA) and slightly tighter clamping margins-use SMAJ6.5CA-13 only when polarity ambiguity or AC coupling justifies the compromise.

What is the maximum allowable PCB trace length between SMAJ6.5CA-13 and the protected node?

Trace inductance directly impacts clamping effectiveness. For sub-10ns ESD events, keep traces under 5mm total loop length (including return path). Longer traces (>10mm) add >10nH inductance, raising peak clamped voltage by up to 350V per 10A/ns di/dt-degrading protection. Use direct placement adjacent to connectors or IC pins, with dedicated ground pour beneath the device.

Is SMAJ6.5CA-13 qualified for automotive AEC-Q200 stress testing?

No-SMAJ6.5CA-13 is not AEC-Q200 qualified. Diodes Incorporated offers the automotive-grade P6SMBJ6.5CA series (AEC-Q200 Grade 1) with identical electrical specs but extended qualification for temperature cycling, humidity, and mechanical shock. For automotive body electronics, use P6SMBJ6.5CA-13 instead; SMAJ6.5CA-13 is intended for industrial and commercial applications.