Taiwan Semiconductor Corporation BZW04-6V4

Overview

BZW04-6V4 from Taiwan Semiconductor is a unidirectional transient voltage suppressor (TVS) diode designed for primary overvoltage protection in DC power rails and signal lines. It features a 6.4 V working stand-off voltage, 7.13–7.88 V breakdown voltage at 10 mA, 400 W peak pulse power (10/1000 μs), 11.3 V maximum clamping voltage at 35.4 A, and operates from −55 °C to +175 °C - deployed in automotive lighting control modules to absorb load-dump transients.

For engineers reviewing the BZW04-6V4 datasheet, BZW04-6V4 pinout, BZW04-6V4 application, or BZW04-6V4 equivalent, key selection criteria include clamping voltage margin vs. protected IC's absolute maximum rating, junction temperature derating above 25 °C, unidirectional polarity marking, DO-41 mechanical fit, and AEC-Q101 qualification status for automotive use.

Technical Context

The BZW04-6V4 employs a silicon avalanche diode structure optimized for fast response (<1 ns) to ESD and electrical fast transients (EFT), with low dynamic impedance enabling tight clamping during 400 W surge events. Its unidirectional configuration provides forward conduction path while suppressing reverse-polarity surges.

Thermal design relies on junction-to-lead resistance of 60 °C/W and junction-to-ambient resistance of 100 °C/W on standard PCB pads; steady-state dissipation is limited to 1 W at 75 °C lead temperature. Reverse leakage remains ≤500 μA at 6.4 V, ensuring minimal standby current impact in battery-powered systems.

Key Specifications

Pinout & Package

Package: DO-204AL (DO-41), axial-leaded, epoxy-molded case with cathode band marking for unidirectional polarity. Leads are pure tin-plated, solderable per J-STD-002, and meet JEDEC JESD201 Class 2 whisker resistance.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ6.0A and P6KE6.8A, the BZW04-6V4 uniquely combines DO-41 axial packaging, AEC-Q101 qualification, and precise 6.4 V VWM - making it the only direct-fit solution for legacy automotive harness-mounted protectors requiring mechanical compatibility and automotive reliability validation.

Availability

BZW04-6V4 is available at Aetrix Electronics and suitable for automotive lighting control, industrial PLC I/O protection, and consumer power adapter output applications requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for BZW04-6V4 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

Taiwan Semiconductor Corporation (TSC) is a vertically integrated analog and discrete semiconductor manufacturer headquartered in Hsinchu, Taiwan, serving global automotive, industrial, and consumer markets since 1979.

The BZW04 series was developed specifically for robust, high-reliability transient suppression in harsh-environment applications - emphasizing AEC-Q101 qualification, wide temperature operation, and repeatable clamping performance across voltage grades.

FAQ

What is the maximum clamping voltage of the BZW04-6V4 during a 400 W surge event?

The BZW04-6V4 exhibits a maximum clamping voltage (VC) of 11.3 V when subjected to its rated peak pulse current of 35.4 A - corresponding to the 400 W surge at the standardized 10/1000 μs waveform. This value is measured and guaranteed per the manufacturer's electrical characteristics table and defines the upper voltage limit imposed on protected circuitry during transient events. The BZW04-6V4 must be selected such that this clamping voltage remains safely below the absolute maximum rating of downstream components.

Is the BZW04-6V4 suitable for bidirectional transient protection?

No, the BZW04-6V4 is a unidirectional TVS diode, intended for DC circuits where polarity is fixed and surges occur primarily in one direction - such as automotive 12 V supply rails. For bidirectional protection (e.g., AC lines or data buses), the BZW04-6V4B variant must be used. The BZW04-6V4 features a cathode band marking and conducts only in reverse breakdown; forward conduction follows standard diode behavior, limiting its use to properly polarized installations.

Does the BZW04-6V4 meet AEC-Q101 qualification standards?

The base BZW04-6V4 is not AEC-Q101 qualified; however, the BZW04-6V4H variant - indicated by the "H" suffix in the ordering code - is fully qualified per AEC-Q101 Rev D for stress tests including HTGB, H3TRB, TC, and ESD. When automotive-grade reliability is required, engineers must specify BZW04-6V4H. The BZW04-6V4 itself is suitable for industrial and commercial applications where qualification is not mandated.

What is the reverse leakage current specification for the BZW04-6V4 at its working voltage?

The BZW04-6V4 specifies a maximum reverse leakage current (ID) of 500 μA when biased at its working stand-off voltage (VWM) of 6.4 V, measured at 25 °C. This low leakage ensures minimal power loss and avoids interference in high-impedance monitoring circuits or battery-backed systems. Leakage decreases further at lower temperatures and increases slightly at elevated junction temperatures, remaining well within design margins for most 12 V applications.

Can the BZW04-6V4 be used in place of the P6KE6.8A without PCB changes?

Yes - the BZW04-6V4 shares the identical DO-204AL (DO-41) axial package, lead spacing, and mechanical dimensions with the P6KE6.8A, enabling direct physical replacement on existing through-hole PCBs. However, differences in VWM (6.4 V vs. 6.8 V), clamping voltage (11.3 V vs. 11.5 V), and AEC-Q101 availability mean functional equivalence must be verified per application requirements. The BZW04-6V4 is not a blind drop-in but a mechanically compatible alternative with distinct electrical tuning.