onsemi SZMMBZ5232BLT1G

Overview

SZMMBZ5232BLT1G from onsemi is a 5.6 V ±5% Zener diode in SOT-23 package, rated for 225 mW power dissipation on FR-5 board at 25°C, with 11 Ω dynamic impedance at 20 mA test current and 5 µA leakage current at 3 V reverse bias. It serves as a precision voltage reference or overvoltage clamp in low-power portable electronics.

For engineers reviewing the SZMMBZ5232BLT1G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance, thermal resistance (556 °C/W), ESD rating (>16 kV HBM), AEC-Q101 qualification, and SOT-23 footprint compatibility for high-density PCB layouts.

Technical Context

This device operates as a two-terminal voltage regulator using avalanche breakdown in silicon PN junction. Its nominal Zener voltage of 5.6 V exhibits near-zero temperature coefficient (≈0 mV/°C) within the 5–6 V range, enabling stable reference performance across −65°C to +150°C junction temperature.

The SOT-23 package features a defined pinout (Pin 1: Anode, Pin 2: No Connection, Pin 3: Cathode), polarity band marking, and Pb-free, RoHS-compliant construction. Thermal derating is linear at 1.8 mW/°C above 25°C on FR-5 board, supporting reliable operation in thermally constrained handheld applications.

Key Specifications

Pinout & Package

SOT-23 (TO-236) surface-mount package: 2.90 mm × 1.30 mm × 1.00 mm body size, void-free thermosetting plastic case, corrosion-resistant finish, UL 94 V-0 flammability rating, cathode indicated by polarity band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with SZMMBZ5232BLT1G, BZX84-C5V6LT1G provides higher power rating but no automotive qualification, while SZBZX84C5V6LT1G matches AEC-Q101 compliance and increases power to 300 mW at the cost of 4 Ω higher dynamic impedance - critical for precision reference stability.

Availability

SZMMBZ5232BLT1G is available at Aetrix Electronics and suitable for automotive sensor modules, USB peripheral protection circuits, and portable device reset logic requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for SZMMBZ5232BLT1G 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

onsemi is a global semiconductor supplier specializing in energy-efficient power management, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

SZMMBZ5232BLT1G belongs to the SZMMBZ52xxBLT1G automotive Zener diode family, designed specifically to meet stringent AEC-Q101 reliability standards for voltage regulation in harsh-environment electronic control units.

FAQ

What is the Zener voltage tolerance of SZMMBZ5232BLT1G?

The SZMMBZ5232BLT1G has a Zener voltage tolerance of ±5% around its nominal 5.6 V rating, meaning the actual measured V_Z falls between 5.32 V and 5.88 V at I_ZT = 20 mA and T_A = 25°C. This tolerance is confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet, and applies across the full operating temperature range.

Is SZMMBZ5232BLT1G suitable for automotive applications?

Yes, SZMMBZ5232BLT1G is explicitly AEC-Q101 qualified and PPAP capable, with manufacturing site and process controls meeting automotive requirements. The "SZ" prefix denotes automotive-grade variants, and the device undergoes extended reliability testing including temperature cycling, high-temperature operating life, and unbiased high-humidity acceleration - all verified per AEC-Q101 standards.

What is the thermal resistance of SZMMBZ5232BLT1G on FR-5 board?

The junction-to-ambient thermal resistance (R_JA) of SZMMBZ5232BLT1G is 556 °C/W when mounted on an FR-5 board per the datasheet's Note 1. This value assumes standard JEDEC test conditions and enables accurate thermal modeling for PCB layout decisions, especially in compact handheld or automotive modules where airflow is limited.

Does SZMMBZ5232BLT1G have a no-connect pin, and how should it be handled?

Yes, SZMMBZ5232BLT1G has Pin 2 designated as "No Connection" per the mechanical outline (Style 8) and electrical characteristics table. This terminal is internally unconnected and must remain electrically floating on the PCB - no solder mask opening, trace, or via should contact it to avoid unintended parasitic coupling or assembly defects.

How does the ESD rating of SZMMBZ5232BLT1G compare to standard commercial Zeners?

SZMMBZ5232BLT1G achieves Class 3 Human Body Model ESD rating (>16 kV), exceeding typical commercial Zeners rated at Class 2 (≥4 kV). This high immunity is achieved through optimized junction design and passivation, making SZMMBZ5232BLT1G suitable for direct integration into ESD-prone interfaces like USB ports or exposed sensor connectors without additional protection components.