Diodes Incorporated MMBZ5228BS-7

Overview

MMBZ5228BS-7 from Diodes Incorporated is a dual isolated 3.9 V, 200 mW surface-mount Zener diode in SOT-363 package, with nominal zener voltage 3.9 V (min 3.71 V, max 4.10 V), zener impedance 23 Ω at 20 mA, and reverse leakage ≤10 μA at 1.0 V, used for precision voltage reference and overvoltage protection in compact power management circuits.

For engineers reviewing the MMBZ5228BS-7 datasheet, MMBZ5228BS-7 pinout, MMBZ5228BS-7 application, or MMBZ5228BS-7 equivalent, key selection criteria include zener voltage tolerance, dynamic impedance at test current, power derating above 25°C, thermal resistance (625 °C/W), and dual-diode isolation for bidirectional clamping or dual-rail reference designs.

Technical Context

This device integrates two electrically isolated Zener diodes in a single ultra-small SOT-363 package, enabling dual-voltage reference or symmetrical transient voltage suppression without inter-device coupling. Each diode operates independently with identical electrical specs: 3.9 V nominal breakdown, 20 mA test current, and 23 Ω dynamic impedance at 1 kHz.

It employs planar die construction for stable voltage regulation under low-current conditions (≤10 μA leakage at 1.0 V reverse bias) and supports automated SMT assembly with RoHS-compliant matte tin plating and moisture sensitivity level 1. Thermal performance is defined for FR4 PCB mounting per AP02001 layout guidelines.

Key Specifications

Pinout & Package

Package: SOT-363 (SC-70-6), molded plastic case with UL 94V-0 flammability rating, 0.006 g weight, and lead-free matte tin plating over Alloy 42 leadframe.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-Zener voltage reference applications.

Compared with BZX84-C3V9LT1G and MMBZ5228B-7, MMBZ5228BS-7 uniquely delivers two isolated 3.9 V Zeners in one SOT-363 package-reducing component count, PCB area, and assembly steps where dual-reference or symmetrical clamping is required.

Availability

MMBZ5228BS-7 is available at Aetrix Electronics and suitable for USB interface protection, 3.3 V LDO reference stabilization, industrial sensor signal conditioning, and low-power microcontroller reset circuits requiring stable component supply and long-term obsolescence management.

Supply support for MMBZ5228BS-7 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, headquartered in Plano, Texas, with design centers across Asia and manufacturing facilities in China, Taiwan, and the U.S.

The MMBZ52xxBS series belongs to Diodes' precision Zener diode product line, engineered specifically for space-constrained, low-power voltage reference and transient suppression applications in portable, industrial, and communications equipment.

FAQ

What is the maximum reverse voltage before breakdown for MMBZ5228BS-7?

The nominal zener voltage is 3.9 V, with a guaranteed range of 3.71 V to 4.10 V at 20 mA test current. Breakdown occurs within this range under specified test conditions; operation below 1.0 V reverse bias yields ≤10 μA leakage, confirming non-conductive behavior outside the zener region.

Can both Zener diodes in MMBZ5228BS-7 be used simultaneously in the same circuit?

Yes - the two diodes are fully electrically isolated, allowing independent biasing and simultaneous operation. For example, one diode can regulate a 3.3 V rail while the other clamps a 5 V auxiliary line, provided total power dissipation remains ≤200 mW and thermal limits are observed.

Is MMBZ5228BS-7 suitable for automotive applications?

Yes - it is qualified for operation from −65 °C to +150 °C and meets RoHS, lead-free, and green compound requirements. While not AEC-Q200 qualified out-of-box, its thermal and electrical specs align with under-dash and infotainment subsystem use cases when validated per customer qualification protocols.

How does the SOT-363 package affect thermal performance compared to SOT-23?

The SOT-363 has higher thermal resistance (625 °C/W) than typical SOT-23 Zeners (~300–400 °C/W) due to smaller pad area and dual-die layout. Derating begins immediately above 25 °C ambient; at 70 °C, maximum allowable power drops to ~140 mW per the published derating curve.