Vishay General Semiconductor - Diodes Division SMBJ188D-M3/I

Overview

SMBJ188D-M3/I from Vishay General Semiconductor is a unidirectional surface-mount transient voltage suppressor (TVS) diode in the SMB (DO-214AA) package, designed for high-energy surge protection on DC power rails and signal lines. It features a 188 V stand-off voltage (VWM), 212–228 V breakdown voltage (VBR) at 1 mA, 600 W peak pulse power (10/1000 μs), clamping voltage of 301 V at 2.03 A, and operates across –55 °C to +150 °C junction temperature.

For engineers reviewing the SMBJ188D-M3/I datasheet, SMBJ188D-M3/I pinout, SMBJ188D-M3/I application, or SMBJ188D-M3/I equivalent, key selection criteria include its precise VWM tolerance, low leakage (<0.5 μA at VWM), M3-grade halogen-free RoHS-compliant construction, and suitability for industrial power supply input protection where sustained overvoltage transients exceed 150 V.

Technical Context

This unidirectional TVS diode operates as a clamping device that remains non-conductive below 188 V and rapidly transitions to low-impedance conduction above its 212–228 V breakdown threshold. Its 301 V clamping voltage at 2.03 A IPPM ensures predictable overvoltage limiting during 10/1000 μs surges, while its 125 °C/W junction-to-ambient thermal resistance reflects performance under standard PCB pad layout conditions.

The SMBJ188D-M3/I uses silicon avalanche technology with a single P-N junction, exhibits ±3.5 % VBR tolerance, and meets J-STD-020 MSL Level 1 reflow requirements (peak 260 °C). Its matte tin-plated leads comply with J-STD-002 and JESD 22-B102 solderability standards, and the M3 suffix confirms JESD 201 Class 2 whisker resistance.

Key Specifications

Pinout & Package

Package: SMB (DO-214AA), molded plastic case per JEDEC DO-214AA standard; cathode indicated by band on end of body; terminals are matte tin-plated for lead-free soldering compatibility.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ188D-M3/I, SMBJ180A-M3/I offers lower clamping but less standoff margin, while SMCJ188A-M3/I delivers identical electrical specs in a thermally superior package-making it suitable for high-duty-cycle surge environments where SMBJ188D-M3/I may approach thermal limits.

Availability

SMBJ188D-M3/I is available at Aetrix Electronics and suitable for industrial power supply input protection, telecom line card surge suppression, and renewable energy inverter DC link protection requiring stable component supply and long-term lifecycle support.

Supply support for SMBJ188D-M3/I 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

Vishay General Semiconductor is a global leader in discrete semiconductors, specializing in diodes, rectifiers, MOSFETs, and protection devices with emphasis on reliability, precision, and automotive/industrial qualification.

The SMBJ series is part of Vishay's TRANSZORB® TVS portfolio, engineered specifically for robust, standardized transient suppression in high-reliability power and interface circuits across harsh-environment applications.

FAQ

What is the breakdown voltage range of the SMBJ188D-M3/I?

The SMBJ188D-M3/I has a guaranteed breakdown voltage (VBR) range of 212 V to 228 V at 1 mA test current, reflecting ±3.5 % tolerance per the Vishay datasheet. This tight specification ensures predictable clamping onset and simplifies coordination with system-level overvoltage protection thresholds. The SMBJ188D-M3/I maintains this VBR consistency across its qualified temperature range.

Is the SMBJ188D-M3/I unidirectional or bidirectional?

The SMBJ188D-M3/I is a unidirectional transient voltage suppressor, indicated by the "D" suffix (as opposed to "CD" for bidirectional variants). It conducts only in reverse bias above VBR, with the cathode marked by a band on the SMB package body. This configuration is optimized for DC rail protection where polarity is fixed and reverse conduction must be strictly controlled.

What does the "M3/I" suffix mean in SMBJ188D-M3/I?

The "M3" suffix denotes halogen-free, RoHS-compliant, industrial-grade construction with JESD 201 Class 2 whisker resistance, while "I" specifies packaging in 13-inch diameter plastic tape and reel with a base quantity of 3200 units. This format ensures compatibility with high-speed pick-and-place equipment and supports extended production runs without manual handling or moisture exposure risks.

Can SMBJ188D-M3/I be used in place of SMBJ180A-M3/I?

No-SMBJ188D-M3/I and SMBJ180A-M3/I are not direct replacements due to differing polarity and voltage ratings: SMBJ188D-M3/I is unidirectional with 188 V VWM, whereas SMBJ180A-M3/I is bidirectional with 180 V VWM. Substitution would require verifying circuit polarity, clamping symmetry, and system-level coordination; the SMBJ188D-M3/I must be used only where unidirectional protection at 188 V standoff is explicitly required.

What is the maximum clamping voltage of SMBJ188D-M3/I at rated surge current?

The SMBJ188D-M3/I has a maximum clamping voltage (VC) of 301 V at its rated peak pulse current (IPPM) of 2.03 A, measured under the standard 10/1000 μs waveform. This value defines the upper voltage limit imposed on the protected circuit during full-rated transient events and is critical for ensuring downstream components remain within their absolute maximum ratings during surge conditions.