onsemi SZMMSZ4686T1G

Overview

SZMMSZ4686T1G from onsemi is a 3.9 V ±5% Zener voltage regulator diode in SOD−123 package, rated for 500 mW power dissipation at TL = 75°C, with 50 µA test current (IZT), 5 µA leakage current at 2 V reverse bias, and −55°C to +150°C operating temperature range-used for precision low-power voltage reference and overvoltage protection in automotive sensor interfaces.

For engineers reviewing the SZMMSZ4686T1G datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage tolerance, dynamic impedance at 20 mA, temperature coefficient near zero-crossing, thermal resistance (RJL = 150°C/W), and AEC−Q101 qualification status for automotive deployment.

Technical Context

This device operates as a two-terminal silicon Zener diode with sharp reverse breakdown at nominal 3.9 V, optimized for stable voltage regulation under low-current conditions (IZT = 50 µA). Its low leakage (IR = 5 µA @ VR = 2 V) and tight voltage tolerance (±5%) support accurate biasing in analog front-ends and reference circuits.

The SOD−123 package enables high-density mounting with verified thermal performance: RJA = 340°C/W and RJL = 150°C/W. It meets AEC−Q101 stress testing requirements and carries Class 3 ESD rating (>16 kV HBM), confirming suitability for harsh automotive environments without external protection circuitry.

Key Specifications

Pinout & Package

SOD−123 surface-mount package: 2-pin, cathode-band marked, dimensions 1.60 × 2.69 × 1.16 mm, void-free thermosetting plastic case, UL 94 V−0 flammability rating.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ4686T1G and BZX84-C3V9LT1G, SZMMSZ4686T1G uniquely combines AEC−Q101 qualification, 500 mW power capability, and 5 µA leakage at 2 V-making it the only option qualified for under-hood automotive voltage reference and clamping where both reliability and thermal headroom are critical.

Availability

SZMMSZ4686T1G is available at Aetrix Electronics and suitable for automotive sensor biasing, industrial analog input protection, and low-power IoT node reference requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for SZMMSZ4686T1G 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 (Semiconductor Components Industries, LLC) is a global semiconductor supplier delivering energy-efficient, intelligent power and sensing solutions for automotive, industrial, cloud, medical, and IoT applications.

SZMMSZ4xxxT1G series is part of onsemi's automotive-qualified Zener regulator portfolio, designed specifically for voltage reference, overvoltage clamping, and bias stabilization in harsh-environment electronic control units.

FAQ

What is the Zener voltage tolerance of SZMMSZ4686T1G?

The SZMMSZ4686T1G has a nominal Zener voltage of 3.9 V with a tolerance of ±5%, meaning its actual breakdown voltage falls between 3.70 V and 4.10 V when tested at IZT = 50 µA and TA = 25°C. This tolerance is confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet. The SZMMSZ4686T1G maintains this specification across its full operating temperature range.

Is SZMMSZ4686T1G qualified for automotive applications?

Yes, SZMMSZ4686T1G is AEC−Q101 qualified and PPAP capable, as explicitly stated in the Features section of the onsemi datasheet. The "SZ" prefix denotes compliance with automotive-specific site and process controls, and the device undergoes stress testing per AEC−Q101 standards. This makes SZMMSZ4686T1G suitable for use in engine control units, body electronics, and other automotive subsystems requiring certified reliability.

What is the maximum power dissipation for SZMMSZ4686T1G?

SZMMSZ4686T1G is rated for 500 mW total power dissipation on FR−5 board at TL = 75°C, with derating of 6.7 mW/°C above that temperature. This value is specified in the Maximum Ratings table and reflects real-world thermal performance under standard PCB layout conditions. The SZMMSZ4686T1G achieves this rating using its SOD−123 package with RJL = 150°C/W, enabling reliable operation in compact, thermally constrained designs.

Does SZMMSZ4686T1G have ESD protection built-in?

Yes, SZMMSZ4686T1G features an ESD rating of Class 3 (>16 kV) per Human Body Model, as documented in the Features section of the onsemi datasheet. This level of robustness means the SZMMSZ4686T1G can withstand electrostatic discharges typical in manufacturing and field environments without parameter degradation or failure-reducing or eliminating the need for external ESD protection components in many interface circuits.

What package type does SZMMSZ4686T1G use?

SZMMSZ4686T1G uses the SOD−123 surface-mount package (Case 425, Style 1), measuring 1.60 × 2.69 × 1.16 mm, with cathode identified by a polarity band. This package is optimized for automated board assembly and high-density layouts. The mechanical outline and marking diagram for SZMMSZ4686T1G are provided on page 6 of the onsemi datasheet, confirming compatibility with standard SOD−123 land patterns.