onsemi MMSZ5226BT3

Overview

MMSZ5226BT3 from onsemi is a 5% tolerance, 3.3 V Zener diode in SOD−123 surface-mount package, rated for 500 mW power dissipation at 75°C ambient, with 28 Ω maximum dynamic impedance at 20 mA test current and 25 µA reverse leakage at 1 V reverse bias - used for precision voltage reference and overvoltage protection in low-power analog circuits.

For engineers reviewing the MMSZ5226BT3 datasheet, pinout, applications, or equivalent options, this page delivers verified electrical specs, thermal derating behavior, cathode/anode terminal roles, automotive-grade AEC−Q101 qualification status, and direct alternatives with documented parameter differences.

Technical Context

This device operates as a two-terminal silicon Zener regulator, maintaining stable reverse breakdown voltage across its cathode–anode junction under controlled current conditions. It exhibits a nominal temperature coefficient of +10 mV/°C near 3.3 V and supports thermal equilibrium operation up to +150°C junction temperature.

The SOD−123 package enables automated placement and reflow soldering with UL 94 V−0 flammability rating and 16 kV HBM ESD robustness. Its 150°C/W junction-to-lead thermal resistance allows effective heat transfer to PCB copper when mounted per recommended footprint.

Key Specifications

Pinout & Package

SOD−123 plastic surface-mount package with cathode indicated by polarity band; dimensions: 2.84 mm × 1.35 mm × 0.94 mm (L × W × H), 0.100″ pitch, UL 94 V−0 rated.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C3V3, MMSZ5226BT3 offers 67% higher power rating and lower dynamic impedance for improved regulation stability; compared with MMSZ5226CT3G, it trades ±2% tolerance for lower unit cost while retaining identical thermal and clamping performance.

Availability

MMSZ5226BT3 is available at Aetrix Electronics and suitable for automotive body electronics, industrial sensor signal conditioning, and portable medical device power management requiring stable component supply and AEC−Q101 compliance.

Supply support for MMSZ5226BT3 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 (formerly ON Semiconductor) is a global semiconductor supplier specializing in energy-efficient power, analog, sensing, and connectivity solutions for automotive, industrial, cloud, and consumer markets.

The MMSZ52xxxT1G Series is designed for general-purpose, medium-current Zener regulation in space-constrained surface-mount applications - emphasizing reliability, thermal stability, and automotive qualification.

FAQ

What is the Zener voltage tolerance for MMSZ5226BT3?

The MMSZ5226BT3 has a ±5% tolerance on its nominal 3.3 V Zener voltage, meaning the actual measured V_Z falls between 3.14 V and 3.47 V when tested at I_ZT = 20 mA and thermal equilibrium. This tolerance is confirmed in the "5% TOLERANCE FG ELECTRICAL CHARACTERISTICS" table on page 3 of the official datasheet. The MMSZ5226BT3 is not rated for tighter tolerances unless replaced with the C-suffix variant (e.g., MMSZ5226CT3G).

Does MMSZ5226BT3 meet automotive qualification standards?

Yes, the MMSZ5226BT3 is AEC−Q101 qualified and PPAP capable, as explicitly stated in the "Features" section of the datasheet. This qualification covers stress testing for temperature cycling, humidity, mechanical shock, and ESD - confirming suitability for automotive applications such as body control modules and sensor interfaces. The SZ-prefix variants (e.g., SZMMSZ5226BT3G) denote additional site-specific controls, but the standard MMSZ5226BT3 retains full AEC−Q101 compliance.

What is the maximum reverse leakage current for MMSZ5226BT3?

The MMSZ5226BT3 specifies a maximum reverse leakage current (I_R) of 25 µA at V_R = 1 V and T_A = 25°C, per the Electrical Characteristics table on page 3. This value remains valid across the full operating temperature range (−55°C to +150°C), though actual leakage increases with temperature - typical curves show ~100 nA at −55°C and ~1 µA at +125°C. Designers should verify leakage impact in ultra-low-power sleep modes.

Can MMSZ5226BT3 be used in place of MMSZ5226BT1G?

Yes, MMSZ5226BT3 is functionally identical to MMSZ5226BT1G except for packaging quantity: both share identical electrical specs, SOD−123 package, Pb−Free construction, and AEC−Q101 qualification. The "T3G" suffix denotes 10,000 units per tape-and-reel, while "T1G" indicates 3,000 units. No circuit-level or thermal differences exist between MMSZ5226BT3 and MMSZ5226BT1G - they are interchangeable in design and layout.

What is the thermal resistance from junction to ambient for MMSZ5226BT3?

The MMSZ5226BT3 has a thermal resistance of R_JA = 340°C/W when mounted on an FR−5 board, as specified in the "MAXIMUM RATINGS" table. This value assumes the minimum recommended footprint per the SOD−123 soldering footprint diagram. In practice, adding thermal relief pads or copper pours reduces effective R_JA; the device's R_JL = 150°C/W indicates superior heat transfer to PCB traces versus ambient air alone.