Diodes Incorporated MMSZ5254BQ-13-F

Overview

MMSZ5254BQ-13-F from Diodes Incorporated is a 27 V, 500 mW surface-mount Zener diode in SOD-123 package, rated for automotive-grade AEC-Q101 reliability, with 5.0 mA test current, 41 Ω dynamic impedance at 1 kHz, and 0.1 µA reverse leakage at 21 V, used for precision voltage regulation in power supply feedback loops and overvoltage protection circuits.

For engineers reviewing the MMSZ5254BQ-13-F datasheet, MMSZ5254BQ-13-F pinout, MMSZ5254BQ-13-F application, or MMSZ5254BQ-13-F equivalent, key selection criteria include nominal Zener voltage tolerance (±3.5%), thermal resistance (338 °C/W), cathode-band polarity marking, automotive qualification status, and SOD-123 footprint compatibility with automated PCB assembly.

Technical Context

This Zener diode operates in reverse breakdown to maintain stable reference voltage under varying load and temperature conditions. Its 27 V nominal Zener voltage exhibits a positive temperature coefficient of +0.08 %/°C per Figure 6, and it delivers regulated output within ±3.5% tolerance across the full 25.65–28.35 V range at 5.0 mA test current.

The device is optimized for low-power voltage clamping and reference applications where compact size and AEC-Q101 qualification are required. With 600 Ω maximum knee impedance at 0.25 mA and 0.1 µA reverse leakage at VR = 21 V, it supports high-impedance sensing and low-quiescent-current designs.

Key Specifications

Pinout & Package

Package: SOD-123 - surface-mount plastic case with matte tin-plated alloy 42 leadframe, cathode band marking, moisture sensitivity level 1, and UL 94V-0 flammability rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C27LT1G and MMBZ5254BS, MMSZ5254BQ-13-F provides higher power rating (500 mW), lower thermal resistance (338 °C/W), and automotive qualification-making it optimal for thermally demanding, safety-critical applications where long-term stability and regulatory compliance are mandatory.

Availability

MMSZ5254BQ-13-F is available at Aetrix Electronics and suitable for automotive engine control units, industrial sensor signal conditioning, and medical infusion pump power monitoring requiring stable component supply with full traceability and AEC-Q101 compliance.

Supply support for MMSZ5254BQ-13-F 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and analog ICs, specializing in high-reliability components for automotive, industrial, and computing markets with ISO/TS 16949 and ISO 14001 certifications.

The MMSZ52xxB series targets cost-effective, space-constrained voltage regulation in automotive and industrial systems, delivering AEC-Q101-qualified Zener performance in miniature SOD-123 packaging.

FAQ

What is the maximum continuous reverse voltage that MMSZ5254BQ-13-F can withstand without breakdown?

The device is rated for 27 V nominal Zener voltage with a guaranteed range of 25.65–28.35 V at 5.0 mA test current. It begins controlled reverse conduction at the lower end of this range and maintains regulation up to its power limit. Sustained reverse voltage above 28.35 V risks exceeding thermal limits unless derated per Figure 1's power derating curve.

How does the SOD-123 package affect thermal performance compared to larger Zener packages?

The SOD-123 package has a junction-to-ambient thermal resistance of 338 °C/W on FR-4 with 1-inch copper pad, significantly higher than TO-236AB (SOT-23) or DO-35 packages. This requires careful PCB layout with thermal relief pads and copper pours to avoid exceeding 150 °C junction temperature at full 500 mW dissipation.

Is MMSZ5254BQ-13-F suitable for use in a precision voltage reference circuit?

No-it is not specified for initial accuracy better than ±3.5% or long-term stability. Its 41 Ω dynamic impedance and +0.08 %/°C temperature coefficient make it appropriate for general-purpose regulation and clamping, but not for sub-0.1% reference applications. For precision references, consider bandgap-based ICs like REF5025.

Does the "Q" suffix in MMSZ5254BQ-13-F indicate AEC-Q101 qualification?

Yes-the "Q" denotes automotive qualification per AEC-Q101 Rev D. This includes stress testing for temperature cycling, high-temperature operating life, and electrostatic discharge robustness. The part meets all requirements for use in non-safety-critical automotive subsystems such as body control modules and infotainment power supplies.