onsemi SZMMSZ5253BT1G

Overview

SZMMSZ5253BT1G from onsemi is a 25 V ±5% Zener diode in SOD−123 package, rated for 500 mW power dissipation at TL = 75°C, with 35 Ω dynamic impedance at 5 mA test current and 0.1 μA reverse leakage at 19 V, used for precision voltage regulation and overvoltage protection in low-power analog sensor interfaces and automotive body control modules.

For engineers reviewing the SZMMSZ5253BT1G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance (±5%), thermal equilibrium specification (TL = 30°C ±1°C), junction-to-lead thermal resistance (150 °C/W), and AEC−Q101 qualification for automotive use.

Technical Context

This device operates as a two-terminal voltage reference diode, conducting in reverse bias above its nominal 25 V Zener voltage with specified dynamic impedance of 35 Ω at IZT = 5 mA and 600 Ω at IZK = 0.25 mA. Its thermal equilibrium Zener voltage measurement ensures stability under steady-state PCB thermal conditions.

The SOD−123 package supports automated assembly and delivers Class 3 ESD robustness (>16 kV HBM), while its 150 °C/W junction-to-lead thermal resistance enables reliable operation up to +150°C junction temperature in thermally constrained layouts.

Key Specifications

Pinout & Package

SOD−123 surface-mount package: 1.60 mm × 2.69 mm × 1.16 mm, void-free thermosetting plastic case with cathode band marking, UL 94 V−0 flammability rating, and 260°C soldering tolerance for 10 seconds.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ5253BT1G, SZMMSZ5253BT1G adds AEC−Q101 qualification and PPAP capability for automotive programs, while BZX84-C24LT1G offers lower dynamic impedance but lacks thermal equilibrium characterization and automotive validation-making SZMMSZ5253BT1G the only option meeting both precision regulation and automotive reliability requirements.

Availability

SZMMSZ5253BT1G is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor signal conditioning, consumer audio power clamping, and medical diagnostic equipment requiring stable component supply with full traceability and long-term lifecycle support.

Supply support for SZMMSZ5253BT1G 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, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

SZMMSZ5253BT1G belongs to the MMSZ52xxxT1G/SZMMSZ52xxxT1G family-engineered for high-reliability voltage regulation in thermally demanding, space-constrained applications where precision, robustness, and automotive qualification are mandatory.

FAQ

What is the Zener voltage tolerance for SZMMSZ5253BT1G?

The SZMMSZ5253BT1G has a nominal Zener voltage of 25 V with a tolerance of ±5%, meaning the actual measured voltage falls between 23.75 V and 26.25 V when tested under thermal equilibrium conditions (TL = 30°C ±1°C). This tolerance is confirmed in the "5% TOLERANCE FG ELECTRICAL CHARACTERISTICS" table on page 3 of the official onsemi datasheet. The SZMMSZ5253BT1G maintains this specification across its full operating temperature range of −55°C to +150°C.

Is SZMMSZ5253BT1G qualified for automotive applications?

Yes, SZMMSZ5253BT1G is AEC−Q101 qualified and PPAP capable, as explicitly stated in the "Features" section of the onsemi datasheet. The "SZ" prefix denotes devices manufactured under automotive-specific process controls and site qualifications. This makes SZMMSZ5253BT1G suitable for use in automotive body control modules, lighting systems, and infotainment power domains where reliability under vibration, thermal cycling, and extended temperature exposure is required.

What is the maximum power dissipation for SZMMSZ5253BT1G on a standard PCB?

SZMMSZ5253BT1G is rated for 500 mW total power dissipation on an FR−5 board at a lead temperature (T_L) of 75°C, with linear derating of 6.7 mW/°C above that temperature. This rating assumes use of the minimum recommended footprint per onsemi's mechanical guidelines. The device's junction-to-lead thermal resistance (R_JL = 150 °C/W) allows it to sustain continuous operation up to +150°C junction temperature when properly mounted on thermally adequate copper areas.

Does SZMMSZ5253BT1G have ESD protection built-in?

Yes, SZMMSZ5253BT1G features an ESD rating of Class 3 (>16 kV) per the Human Body Model (HBM), as documented in the "Features" section of the onsemi datasheet. This level of ESD robustness eliminates the need for additional discrete ESD protection components in many board-level designs, particularly in handheld or connector-exposed applications. The rating applies to both terminals and was verified during AEC−Q101 qualification testing.

What is the reverse leakage current specification for SZMMSZ5253BT1G?

The reverse leakage current (I_R) for SZMMSZ5253BT1G is specified as 0.1 μA maximum at a reverse voltage (V_R) of 19 V, per the "5% TOLERANCE FG ELECTRICAL CHARACTERISTICS" table on page 3 of the datasheet. This low leakage supports ultra-low-power operation in battery-backed systems and precision analog circuits where standby current must be minimized. The value is measured at T_A = 25°C and remains stable across the full −55°C to +150°C operating range.