onsemi SZMMSZ3V0T1G

Overview

SZMMSZ3V0T1G from onsemi is a 3.0 V ±5% Zener voltage regulator diode in SOD−123 package, rated for 500 mW power dissipation at 75°C, with 95 Ω maximum dynamic impedance at 5 mA test current and 10 µA maximum reverse leakage at 1 V reverse bias. It serves as a precision voltage reference or overvoltage clamp in low-power analog sensor interfaces and microcontroller I/O protection circuits.

For engineers reviewing the SZMMSZ3V0T1G datasheet, pinout, applications, or equivalent options, key selection criteria include its AEC−Q101 qualification, Class 3 ESD rating (>16 kV HBM), tight ±5% V_Z tolerance, and thermal derating behavior across −55°C to +150°C junction temperature range.

Technical Context

This device operates in reverse breakdown mode to maintain stable 3.0 V regulation under controlled Zener current (I_ZT = 5 mA). Its 95 Ω dynamic impedance (Z_ZT) and 10 µA reverse leakage at 1 V ensure low noise and minimal standby current draw in voltage reference applications.

The SOD−123 package supports automated assembly and delivers 340°C/W junction-to-ambient thermal resistance. Its cathode band marking and Pb−free construction comply with automotive-grade reliability requirements per AEC−Q101 and UL 94 V−0 flammability standard.

Key Specifications

Pinout & Package

SOD−123 surface-mount package: 2-terminal, 1.60 × 2.69 × 1.16 mm body, cathode indicated by polarity band. Designed for high-density placement and reflow compatibility up to 260°C for 10 seconds.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MMSZ3V0T1G and BZX84-C3V0, SZMMSZ3V0T1G uniquely combines AEC−Q101 qualification, SOD−123 miniaturization, and 95 Ω Z_ZT, making it optimal for next-generation automotive and industrial edge devices requiring both reliability and density.

Availability

SZMMSZ3V0T1G is available at Aetrix Electronics and suitable for automotive sensor modules, industrial analog input protection circuits, and low-power IoT node voltage references requiring stable component supply, full traceability, and long-term lifecycle support.

Supply support for SZMMSZ3V0T1G 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 delivering energy-efficient silicon solutions for automotive, industrial, cloud, medical, and IoT applications.

SZMMSZ3V0T1G belongs to the AEC−Q101-qualified MMSZxxxT1G family of 500 mW Zener regulators designed specifically for high-reliability voltage reference and overvoltage protection in harsh-environment electronics.

FAQ

What is the Zener voltage tolerance for SZMMSZ3V0T1G?

The SZMMSZ3V0T1G has a nominal Zener voltage of 3.0 V with a tolerance of ±5%, meaning the actual measured V_Z falls between 2.85 V and 3.15 V when tested at I_ZT = 5 mA and T_A = 25°C. This tolerance is guaranteed across the full operating temperature range and is critical for precision reference applications where voltage stability directly impacts measurement accuracy.

Is SZMMSZ3V0T1G suitable for automotive applications?

Yes, SZMMSZ3V0T1G is AEC−Q101 qualified and PPAP capable, with manufacturing and testing performed under automotive-grade quality systems. The "SZ" prefix denotes compliance with unique site and control change requirements mandated for automotive supply chains, making SZMMSZ3V0T1G appropriate for engine control, body electronics, and ADAS subsystems.

What is the maximum power dissipation of SZMMSZ3V0T1G at 100°C ambient?

At ambient temperature (T_A) = 100°C, SZMMSZ3V0T1G's power dissipation must be derated from its 500 mW rating at 75°C using the 6.7 mW/°C derating factor. This yields P_D = 500 mW − (100 − 75) × 6.7 mW = 332.5 mW. Exceeding this limit risks thermal runaway and permanent degradation of the Zener characteristic.

Does SZMMSZ3V0T1G have a specified forward voltage?

Yes, SZMMSZ3V0T1G specifies a maximum forward voltage (V_F) of 0.95 V at I_F = 10 mA and T_A = 25°C. This parameter is relevant when the device is used bidirectionally-for example, as an ESD clamp-where low forward conduction voltage helps limit positive transients without loading the signal path.

How does the thermal resistance of SZMMSZ3V0T1G affect PCB layout?

SZMMSZ3V0T1G has a junction-to-ambient thermal resistance (R_JA) of 340°C/W on FR−5 board. To maintain safe junction temperatures, designers must minimize local copper area restrictions around the SOD−123 pad and avoid enclosing the device in thermally isolated zones. Adding thermal vias beneath the cathode/anode pads can reduce effective R_JA and extend usable power headroom.