Taiwan Semiconductor Corporation BZX584B56 RSG

Overview

BZX584B56 RSG from Taiwan Semiconductor is a surface-mount Zener diode with nominal zener voltage 56 V, ±2% tolerance, 150 mW power dissipation, and SOD-523F package. It provides precise voltage regulation in low-power analog circuits, ESD protection clamping, and reference voltage generation for sensor signal conditioning.

For engineers reviewing the BZX584B56 RSG datasheet, BZX584B56 RSG pinout, BZX584B56 RSG application, or BZX584B56 RSG equivalent, key selection criteria include zener voltage accuracy (54.6–57.4 V), low leakage current (≤0.1 µA at 43 V), temperature coefficient (+43 mV/°C), and thermal resistance (833 °C/W) in ultra-small SOD-523F footprint.

Technical Context

The BZX584B56 RSG operates as a single-die, cathode-banded Zener diode optimized for stable reverse-breakdown regulation at 56 V with 2 mA test current. Its junction temperature range spans −55 °C to +150 °C, and it meets JESD201 Class 1A whisker resistance and J-STD-020 Moisture Sensitivity Level 1.

Designed for high-reliability SMT assembly, the device features matte tin-plated leads compliant with J-STD-002 solderability, UL 94V-0 molding compound, and halogen-free construction per IEC 61249-2-21. Its 1.30 mg mass supports automated pick-and-place handling.

Key Specifications

Pinout & Package

Package: SOD-523F - ultra-miniature plastic surface-mount case with cathode band marking; dimensions 1.2 mm × 0.8 mm × 0.6 mm; weight ≈ 1.30 mg.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar Zener diode applications.

Compared with MMBZ5256B and BZX384-B56, the BZX584B56 RSG delivers identical voltage accuracy in the smallest available footprint with lowest thermal resistance among sub-200 mW 56 V Zeners, making it optimal for miniaturized battery-powered systems.

Availability

BZX584B56 RSG is available at Aetrix Electronics and suitable for industrial sensor signal conditioning, low-power microcontroller reset circuits, ESD protection clamps, and precision DAC reference applications requiring stable component supply and consistent parametric performance across production batches.

Supply support for BZX584B56 RSG 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, analog ICs, and protection components for industrial, automotive, and consumer markets.

The BZX584 series is part of TSC's precision Zener diode product line engineered for high-accuracy voltage regulation in compact SMT applications, emphasizing tight tolerance, low leakage, and robust reliability under thermal cycling.

FAQ

What is the maximum reverse voltage the BZX584B56 RSG can withstand before breakdown?

The BZX584B56 RSG has a nominal zener voltage of 56 V with guaranteed minimum and maximum values of 54.6 V and 57.4 V respectively at 2 mA test current. Its absolute maximum reverse voltage is defined by its breakdown characteristic - operation beyond 57.4 V at rated current will cause sustained conduction, but the device remains within safe operating limits up to its 150 mW power dissipation limit. Exceeding this power causes thermal runaway.

Does the BZX584B56 RSG require derating at elevated ambient temperatures?

Yes. The BZX584B56 RSG must be derated linearly above 25 °C ambient: its 150 mW power rating decreases by 1.8 mW/°C (150 mW ÷ 83.3 °C thermal rise). At 85 °C ambient, maximum allowable dissipation drops to approximately 42 mW. This derating is critical for reliable operation in enclosed industrial enclosures or near heat-generating components.

Is the BZX584B56 RSG compatible with lead-free reflow profiles?

Yes. The BZX584B56 RSG uses matte tin-plated terminals qualified to J-STD-002 for solderability and is rated for moisture sensitivity level 1 per J-STD-020, meaning it can be subjected directly to standard lead-free reflow (peak 260 °C) without baking. Its UL 94V-0 molding compound also withstands repeated thermal excursions without delamination.

How does the +43 mV/°C temperature coefficient affect circuit performance?

The +43 mV/°C temperature coefficient means the BZX584B56 RSG's zener voltage increases by 43 mV per degree Celsius rise in junction temperature. In precision references, this drift must be compensated - for example, by pairing with a negative-TC component or using it in a temperature-compensated divider. At 56 V, this equates to ~0.077%/°C drift, which is manageable in non-critical regulation but requires modeling in metrology-grade designs.

Can the BZX584B56 RSG be used in forward-bias applications?

The BZX584B56 RSG is optimized for reverse-bias zener operation and is not characterized for forward conduction. While its forward voltage is ~0.9 V at 10 mA (per Fig.1), forward use is discouraged - it lacks guaranteed parameters like forward voltage consistency or surge current rating. For forward rectification, dedicated signal diodes such as 1N4148WS should be selected instead of the BZX584B56 RSG.