Diodes Incorporated SMAJ5.0A-13-F

Overview

SMAJ5.0A-13-F from Diodes Incorporated is a unidirectional 400W surface-mount transient voltage suppressor (TVS) diode designed for primary overvoltage protection in DC power lines and signal interfaces. It features a 5.0V reverse standoff voltage, 6.4V minimum breakdown voltage at 10mA, 9.2V maximum clamping voltage at 43.5A peak pulse current, and operates across –55°C to +150°C. Used in automotive infotainment power rails to suppress load dump and ISO 7637-2 transients.

For engineers reviewing the SMAJ5.0A-13-F datasheet, SMAJ5.0A-13-F pinout, SMAJ5.0A-13-F application, or SMAJ5.0A-13-F equivalent, key selection criteria include clamping voltage margin vs. protected IC V_MAX, peak pulse current capability under 8.3ms half-sine waveform, unidirectional polarity alignment with DC rail direction, and SMA package thermal performance under sustained surge duty cycles.

Technical Context

This TVS diode employs glass-passivated silicon junction construction to achieve sub-nanosecond response time and stable clamping under repetitive surge stress. Its unidirectional configuration provides forward conduction path during negative transients while blocking reverse leakage below 800µA at 5.0V standoff.

The device complies with IEC 61000-4-2 (ESD), IEC 61000-4-4 (EFT), and ISO 7637-2 (automotive transients) when applied with appropriate PCB layout and series impedance. Thermal derating follows a linear curve from 1.0W at 75°C lead temperature down to zero at 150°C junction temperature.

Key Specifications

Pinout & Package

Package: SMA (DO-214AC), molded plastic case with UL 94V-0 flammability rating, cathode band marking for unidirectional polarity identification. Moisture sensitivity level 1 (J-STD-020).

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMAJ5.0A-E3/61, the -13-F offers optimized tape-and-reel delivery for high-volume SMT lines; versus 1.5SMC5.0A, it trades surge capacity for space-constrained placement in compact modules where 400W meets ISO 7637-2 Class III requirements.

Availability

SMAJ5.0A-13-F is available at Aetrix Electronics and suitable for automotive infotainment systems, industrial PLC input modules, and USB host port protection requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for SMAJ5.0A-13-F 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, specializing in high-reliability protection, power management, and signal integrity solutions for automotive, industrial, and computing markets.

This device belongs to the SMAJ series of surface-mount TVS diodes engineered specifically for robust transient immunity in harsh environments-designed to meet AEC-Q101 stress test requirements and support PPAP documentation for automotive Tier 1 suppliers.

FAQ

Is SMAJ5.0A-13-F suitable for bidirectional signal line protection?

No. SMAJ5.0A-13-F is unidirectional and must be used only on DC-biased lines where polarity is fixed. For bidirectional applications like RS-485 or AC-coupled USB, the bidirectional variant SMAJ5.0CA-13-F (with "C" suffix) is required, which has symmetrical clamping in both directions and no cathode band marking.

What is the maximum allowable PCB trace length between SMAJ5.0A-13-F and the protected IC?

Trace inductance must be minimized to preserve clamping speed. For optimal performance, keep total trace length from cathode to protected IC input and anode to ground plane under 5mm. Longer traces increase voltage overshoot due to L·di/dt; measured data shows >10mm adds ≥1.2V overshoot at 43.5A/10ns rise time.

Does SMAJ5.0A-13-F require derating for operation at 100°C ambient?

Yes. At 100°C ambient, the peak pulse power must be reduced to 280W (70% of 400W) per Figure 1 derating curve. This is due to junction temperature limits; the device remains fully functional but cannot sustain full-rated surge energy without exceeding 150°C TJ.

Can SMAJ5.0A-13-F replace P6KE5.0A in an existing design?

Only with layout review. Both suppress 5V transients, but SMAJ5.0A-13-F uses SMA package (4.6mm × 2.9mm) versus P6KE5.0A's DO-15 (7.1mm × 2.5mm). The SMA's lower thermal mass requires tighter copper pour design for heat dissipation during repetitive surges, and its 5000-piece reel format differs from DO-15's bulk packaging.