Diodes Incorporated SMBJ8.5CA-13-F

Overview

SMBJ8.5CA-13-F from Diodes Incorporated is a bi-directional 600W surface-mount transient voltage suppressor (TVS) diode designed for robust overvoltage protection in DC power rails and signal lines. It features a 8.5V reverse standoff voltage (VRWM), 9.44–10.82V breakdown voltage (VBR) at 1mA, 14.4V maximum clamping voltage (VC) at 41.7A peak pulse current, and operates across –55°C to +150°C. It is used in industrial power supplies to safeguard microcontrollers against ESD and lightning-induced surges.

For engineers reviewing the SMBJ8.5CA-13-F datasheet, SMBJ8.5CA-13-F pinout, SMBJ8.5CA-13-F application, or SMBJ8.5CA-13-F equivalent, key selection criteria include clamping voltage margin relative to protected IC VCC, unidirectional vs. bi-directional polarity requirements for AC-coupled interfaces, thermal derating above +25°C, and compatibility with SMB package reflow profiles.

Technical Context

This bi-directional TVS uses glass-passivated silicon junction construction to achieve fast response (<1 ns) to transients while sustaining 600W non-repetitive peak pulse power per the 10/1000μs waveform. Its symmetrical I-V characteristic enables protection of both polarities without external polarity management.

The device exhibits low leakage (<10 μA at VRWM), tight VBR tolerance (±6.5%), and stable clamping performance up to TJ = +150°C - critical for automotive body control modules and outdoor-rated IoT gateways where ambient temperature swings exceed 100°C.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), surface-mount, molded plastic case with UL 94V-0 flammability rating; dimensions: 3.30–3.94 mm (L) × 4.06–4.57 mm (W) × 1.96–2.21 mm (H); weight ≈ 0.1 g.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ8.5A-13-F, the bi-directional version eliminates polarity dependency at the cost of slightly higher leakage; compared with SMAJ8.5CA, it delivers 50% higher surge energy handling and superior thermal robustness in industrial enclosures.

Availability

SMBJ8.5CA-13-F is available at Aetrix Electronics and suitable for industrial motor drives, automotive body control modules, outdoor IoT gateways, and medical diagnostic equipment requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for SMBJ8.5CA-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, headquartered in Plano, Texas, with design centers and manufacturing facilities across Asia and the Americas.

This part belongs to Diodes' SMBJ series of high-power TVS diodes, engineered specifically for board-level protection against IEC 61000-4-2, -4-4, and -4-5 threats in harsh industrial and automotive environments.

FAQ

What is the difference between SMBJ8.5CA-13-F and SMBJ8.5A-13-F?

The "C" suffix denotes bi-directional operation: SMBJ8.5CA-13-F protects both positive and negative transients without polarity sensitivity, while SMBJ8.5A-13-F is uni-directional and requires correct anode/cathode orientation. Bi-directional units exhibit doubled leakage current specification (≤10 μA) for VRWM ≤10V per datasheet Note 10.

Can SMBJ8.5CA-13-F be used in place of P6KE8.5CA?

No - P6KE8.5CA is a through-hole DO-15 package with 600W rating but slower response time (>5 ns), larger footprint, and different thermal mass. SMBJ8.5CA-13-F offers superior high-frequency transient suppression and SMT manufacturability, but cannot be substituted without PCB layout revision and revalidation of surge test margins.

What is the maximum allowable PCB trace length between SMBJ8.5CA-13-F and the protected IC?

To maintain sub-1 ns response, keep traces under 5 mm total length (including vias and bends) and avoid stubs. Longer traces add inductance that degrades clamping performance - measured data shows >10 mm increases VC by ≥12% at 41.7A due to L·di/dt voltage overshoot.

Does SMBJ8.5CA-13-F require derating at elevated ambient temperatures?

Yes - its peak pulse power must be linearly derated above +25°C at 4.8 W/°C (per datasheet PDER). At +85°C ambient, usable peak power drops to 312W. For continuous operation near +125°C, verify junction temperature using θJA and steady-state power dissipation limits (PM(AV) = 5.0W @ TL = +75°C).