STMicroelectronics BZW04-58RL

Overview

BZW04-58RL from STMicroelectronics is a unidirectional transient voltage suppression (TVS) diode in DO-15 package, designed to clamp ESD and surge transients up to 400 W (10/1000 µs) with a stand-off voltage of 58 V, clamping voltage of 92 V at 4.3 A, and junction temperature rating up to +175 °C. It protects power rails and I/O lines in industrial power supplies and telecom interfaces.

For engineers reviewing the BZW04-58RL datasheet, BZW04-58RL pinout, BZW04-58RL application, or BZW04-58RL equivalent, key selection criteria include clamping voltage at rated surge current, dynamic resistance, leakage current below 1 µA at 25 °C, thermal derating above 25 °C, and compliance with IEC 61000-4-2 level 4 (30 kV contact/air discharge) and IEC 61000-4-4 level 4 (4 kV).

Technical Context

This TVS diode uses planar silicon technology to achieve low leakage (<1 µA at VRM), stable breakdown voltage (VBR = 58.1–64.6 V), and high junction temperature operation (Tj = −55 to +175 °C). Its unidirectional configuration provides forward conduction path for DC-biased lines while suppressing reverse-polarity surges.

The device delivers 400 W peak pulse power at 25 °C under 10/1000 µs waveform, derating to 230 W at Tj = 175 °C. Dynamic resistance (RD = 4.79 Ω) and clamping voltage (VCL = 92 V @ IPP = 4.3 A) are specified per IEC 61000-4-2 and IEC 61000-4-4 test conditions.

Key Specifications

Pinout & Package

DO-15 (JEDEC DO-204AC) axial-leaded package with matte tin-plated leads. Cathode indicated by band marking; anode is unmarked end. Compatible with wave and reflow soldering per J-STD-020 MSL level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SMBJ58A and P6KE56A, BZW04-58RL offers tighter VBR (58.1–64.6 V), lower leakage (<1 µA), and superior thermal stability up to +175 °C-critical for high-reliability industrial and automotive power stages where long-term parametric drift must be minimized.

Availability

BZW04-58RL is available at Aetrix Electronics and suitable for industrial power supplies, telecom interface protection, automotive body control modules, and smart meter converter stages requiring stable component supply across extended temperature ranges and multi-year production cycles.

Supply support for BZW04-58RL 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.

The BZW04 series belongs to ST's high-reliability TVS portfolio, engineered specifically for robust transient suppression in harsh-environment power conversion and communication infrastructure where long-term stability and high-temperature operation are mandatory.

FAQ

What is the maximum surge current the BZW04-58RL can handle under IEC 61000-4-4 conditions?

The BZW04-58RL sustains 4.3 A peak pulse current (IPP) under 10/1000 µs waveform at 25 °C, delivering 400 W clamped power. At 8/20 µs (IEC 61000-4-4), it handles up to 19 A with VCL = 121 V, confirmed in Table 2 of DS0660 Rev 4. Derating applies above 25 °C per Figure 3.

Is the BZW04-58RL suitable for bidirectional signal line protection?

No - BZW04-58RL is unidirectional and intended for DC-biased lines like power rails. For bidirectional protection (e.g., RS-485, USB), use the BZW04-58B variant, which features symmetrical clamping and dual cathode/anode terminals. The "RL" suffix denotes reel packaging but does not affect polarity.

How does the junction temperature affect clamping voltage performance?

VCL increases linearly with junction temperature per coefficient αT = 10.4 × 10⁻⁴ /°C. At Tj = 125 °C, VCL rises ~10.4% above its 25 °C value (92 V → ~101.6 V). This is calculated using VCL at Tj = VCL at 25 °C × (1 + αT × (Tj − 25)), as defined in Note 2 of Table 2.

What is the recommended PCB layout practice to maximize thermal performance?

Mount the DO-15 package with ≥1 cm² copper area under each lead (per Figure 12), using thermal vias to inner ground planes. Maintain ≥2 mm clearance from adjacent heat sources. Rth(j-a) drops from 4.5 °C/W (no copper) to <2.5 °C/W with 3 cm² total copper, directly improving surge endurance at elevated ambient temperatures.