Taiwan Semiconductor Corporation BZW04-19

Overview

BZW04-19 from Taiwan Semiconductor is a unidirectional transient voltage suppressor (TVS) diode designed for high-energy surge protection in DC power rails and signal lines. It features a 18.8 V working stand-off voltage, 20.9–23.1 V breakdown voltage at 1 mA, 30.6 V maximum clamping voltage at 13.0 A peak pulse current, and 400 W peak pulse power rating per 10/1000 μs waveform - deployed in automotive lighting control and industrial sensor interface circuits.

For engineers reviewing the BZW04-19 datasheet, BZW04-19 pinout, BZW04-19 application, or BZW04-19 equivalent, key selection criteria include clamping voltage margin vs. protected IC's absolute maximum rating, leakage current at operating voltage, thermal derating above 25°C ambient, and DO-41 lead-form compatibility with manual or wave-solder assembly.

Technical Context

The BZW04-19 operates as a silicon avalanche diode with unidirectional polarity, triggered when reverse voltage exceeds its specified breakdown range. Its low dynamic impedance ensures rapid voltage clamping during ESD or inductive switching transients, while sub-1 μA reverse leakage at 18.8 V supports low-power system standby integrity.

Designed for single-pulse surge immunity per IEC 61000-4-5 (10/1000 μs), it sustains 13.0 A peak impulse current with 30.6 V clamping - enabling robust protection of 24 V industrial controllers and automotive body electronics without compromising downstream voltage tolerance.

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 JESD 201 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 SMBJ19A and P6KE19A, the BZW04-19 offers identical clamping performance in a smaller DO-41 package with lower R_θJL (60 °C/W), enabling tighter thermal management in compact industrial enclosures without sacrificing surge rating.

Availability

BZW04-19 is available at Aetrix Electronics and suitable for automotive lighting control, industrial PLC input protection, and DC power rail protection requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for BZW04-19 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 semiconductor manufacturer specializing in discrete power devices, TVS diodes, rectifiers, and MOSFETs, with global distribution and AEC-Q101 qualification capabilities.

The BZW04 series is part of TSC's high-reliability transient suppression portfolio, engineered specifically for automotive and industrial applications demanding consistent clamping behavior, low leakage, and proven surge endurance under harsh thermal and electrical stress.

FAQ

What is the maximum clamping voltage of the BZW04-19 under standard surge conditions?

The BZW04-19 has a maximum clamping voltage (V_C) of 30.6 V when subjected to a 10/1000 μs waveform at 13.0 A peak pulse current. This value is measured per ANSI/IEEE C62.35 and ensures predictable voltage limiting during standardized surge events. The BZW04-19 maintains this clamping performance across its full operating temperature range of –55 °C to +175 °C, making it suitable for under-hood automotive use.

Is the BZW04-19 unidirectional or bidirectional, and how is polarity identified?

The BZW04-19 is a unidirectional TVS diode, indicated by the absence of "B" suffix (e.g., BZW04-19B would be bidirectional). Polarity is marked by a cathode band on the DO-41 package body, aligning with standard diode convention: cathode connects to the protected line, anode to ground. This configuration provides asymmetric protection optimized for DC rails where reverse voltage is not expected.

Does the BZW04-19 meet automotive reliability standards?

Yes - the BZW04-19H variant is AEC-Q101 qualified, covering stress tests including high-temperature reverse bias (HTRB), temperature cycling, and ESD (HBM ≥8 kV, CDM ≥1 kV). While the base BZW04-19 is not automatically qualified, the "H" suffix denotes full automotive validation. Engineers specifying BZW04-19 for automotive use should select BZW04-19H to ensure compliance with vehicle-level reliability requirements.

What is the thermal resistance from junction to lead (R_θJL) for the BZW04-19?

The BZW04-19 has a typical junction-to-lead thermal resistance (R_θJL) of 60 °C/W, measured with 9.5 mm lead lengths. This low value enables efficient heat transfer to PCB copper pours or chassis mounts, supporting sustained operation near its 175 °C maximum junction temperature. When designing for high ambient environments, this R_θJL allows more precise thermal modeling than relying solely on R_θJA (100 °C/W).

Can the BZW04-19 replace the P6KE19A in an existing design?

The BZW04-19 is not a direct pin-compatible replacement for P6KE19A due to differing DO-41 vs. DO-15 package dimensions and lead spacing. While both share similar electrical specs (V_WM, V_C, P_PK), mechanical integration requires PCB footprint revision. For legacy P6KE19A designs, BZW04-19 offers improved thermal performance but mandates layout update - verify creepage/clearance and solder joint reliability post-change.