Diodes Incorporated MMBZ5226BS-7

Overview

MMBZ5226BS-7 from Diodes Incorporated is a dual-isolated 3.3 V, 200 mW surface-mount Zener diode in SOT-363 package, with nominal zener voltage 3.3 V (min 3.14 V, max 3.47 V), zener test current 20 mA, dynamic impedance 28 Ω at I_ZT, and reverse leakage ≤25 μA at 1.0 V. It provides precision voltage reference and overvoltage clamping in space-constrained power management circuits.

For engineers reviewing the MMBZ5226BS-7 datasheet, MMBZ5226BS-7 pinout, MMBZ5226BS-7 application, or MMBZ5226BS-7 equivalent, key selection criteria include zener voltage tolerance (±3.6%), low dynamic impedance for stable regulation, dual-diode isolation for bidirectional protection, and SOT-363 footprint compatibility with high-density PCB layouts.

Technical Context

This device integrates two independent Zener diodes in a single ultra-small SOT-363 package, enabling compact dual-rail voltage referencing or bidirectional transient suppression without inter-device coupling. Each diode operates with identical electrical specs and shares no internal connection.

It is rated for 200 mW total power dissipation at 25°C ambient, derating linearly to zero at 150°C junction temperature, and exhibits thermal resistance of 625°C/W when mounted on FR4 with recommended pad layout. Reverse leakage remains ≤25 μA up to 1.0 V, ensuring minimal standby current draw.

Key Specifications

Pinout & Package

SOT-363 (SC-70-6) plastic surface-mount package with six terminals: two anodes (A1, A2), two cathodes (C1, C2), and two no-connect (NC) pins. Molded case meets UL 94V-0 flammability rating; moisture sensitivity level 1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX84-C3V3 and MMBZ5226B, MMBZ5226BS-7 uniquely delivers dual isolated 3.3 V Zeners in SOT-363-reducing component count by 50%, eliminating layout-induced crosstalk, and enabling true bidirectional protection without external routing compromises.

Availability

MMBZ5226BS-7 is available at Aetrix Electronics and suitable for USB interface protection, low-voltage microcontroller reference design, industrial sensor signal conditioning, and automotive body control module clamp circuits requiring stable component supply and long-term obsolescence management.

Supply support for MMBZ5226BS-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, manufacturing, and sales operations across Asia, Europe, and North America.

The MMBZ52xxBS series belongs to Diodes' precision Zener diode product line, engineered specifically for high-reliability, space-constrained voltage regulation and transient suppression in portable, industrial, and automotive electronics.

FAQ

What is the maximum continuous reverse voltage that can be applied before breakdown?

The MMBZ5226BS-7 has a nominal zener voltage of 3.3 V with a guaranteed range of 3.14 V to 3.47 V at 20 mA test current. Breakdown begins at the lower limit (3.14 V), and operation above 3.47 V under sustained DC conditions exceeds specification and risks thermal runaway. For reliable clamping, design margins should keep applied reverse voltage below 3.47 V.

Can both Zener diodes be used simultaneously without interference?

Yes - the two Zener diodes are fully isolated internally, with no shared junctions or substrate coupling. Electrical testing confirms independent forward and reverse characteristics for each diode pair (C1/A1 and C2/A2). Cross-talk between channels is negligible (<0.1% voltage shift) even under simultaneous 20 mA bias.

Is the SOT-363 package compatible with standard reflow profiles for lead-free assembly?

Yes - the device is qualified for lead-free reflow per J-STD-020D Level 1 moisture sensitivity, with peak temperature tolerance up to 260°C. Its matte tin plating and UL 94V-0 mold compound ensure robust performance through standard Pb-free SAC305 reflow cycles without delamination or solder joint voiding.

How does the 28 Ω zener impedance affect regulation accuracy under load variation?

At 20 mA test current, 28 Ω impedance means a 1 mA load change induces ~28 mV output shift. For example, reducing load current from 20 mA to 15 mA increases V_Z by approximately 140 mV (5 mA × 28 Ω), resulting in final regulation of ~3.44 V - still within the 3.47 V upper limit and suitable for 3.3 V ±5% systems.