onsemi MM3Z56VB

Overview

MM3Z56VB from onsemi is a 56 V, ±2% tolerance Zener diode in SOD−323FL package, rated for 200 mW power dissipation and 188 Ω dynamic impedance at 2 mA test current, used for precision voltage regulation and overvoltage protection in low-power analog circuits.

For engineers reviewing the MM3Z56VB datasheet, pinout, applications, or equivalent options, key selection criteria include Zener voltage accuracy (54.88–57.12 V), low leakage current (≤45 nA at 39.2 V), thermal resistance (595 °C/W), and SOD−323FL footprint compatibility with space-constrained PCB layouts.

Technical Context

The MM3Z56VB operates as a two-terminal voltage reference device, maintaining stable reverse breakdown voltage across its cathode-anode terminals under controlled current conditions. Its Zener impedance of 188 Ω at 2 mA and 400 Ω at 0.5 mA reflects voltage regulation stability under varying load currents.

Designed for surface-mount use in ambient temperatures from −65 °C to +150 °C, it features matte tin (Pb-free) termination and complies with JEDEC SOD−323FL mechanical outline CASE 477AB, ensuring reliable solderability and thermal performance in compact consumer and industrial electronics.

Key Specifications

Pinout & Package

SOD−323FL package: ultra-compact 2-pin surface-mount plastic case (1.7 mm × 1.25 mm × 0.95 mm), matte tin (Pb-free) finish, cathode marked by band.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX384-B56 and MMSZ5256B, the MM3Z56VB offers the smallest PCB footprint and tightest voltage tolerance in its 200 mW class, making it optimal for space-limited, high-accuracy applications like portable medical sensors and precision instrumentation front-ends.

Availability

MM3Z56VB is available at Aetrix Electronics and suitable for USB power protection, industrial sensor reference, low-power battery monitoring, and LED driver overvoltage clamping requiring stable component supply and consistent parametric performance across production lots.

Supply support for MM3Z56VB 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.

The MM3Z56VB belongs to onsemi's MM3Z series of miniature Zener diodes, engineered specifically for high-accuracy voltage regulation in space-constrained, low-power electronic systems where precision, reliability, and RoHS compliance are critical.

FAQ

What is the Zener voltage tolerance of the MM3Z56VB?

The MM3Z56VB has a ±2% Zener voltage tolerance, meaning its specified breakdown voltage ranges from 54.88 V to 57.12 V at the test current of 2 mA. This tight tolerance enables high-accuracy voltage reference and clamping functions without additional calibration. The MM3Z56VB achieves this specification under standard test conditions defined in the onsemi datasheet Rev. 3 (August 2023).

What package type does the MM3Z56VB use?

The MM3Z56VB uses the SOD−323FL package (JEDEC CASE 477AB), a miniature surface-mount plastic case measuring 1.7 mm × 1.25 mm × 0.95 mm with matte tin (Pb-free) terminations. This package supports automated placement and reflow soldering while minimizing PCB real estate. The MM3Z56VB's compact size makes it ideal for wearable electronics and dense IoT module designs.

What is the maximum power dissipation rating for the MM3Z56VB?

The MM3Z56VB is rated for a maximum power dissipation of 200 mW at 25 °C ambient temperature. Derating is required above 25 °C per the thermal resistance value of 595 °C/W, reducing usable power by approximately 0.34 mW/°C. This rating defines the safe continuous operating current limit (~3.6 mA at 56 V) before thermal runaway risk increases. The MM3Z56VB must be used within this boundary to ensure long-term reliability.

How does the MM3Z56VB perform at elevated temperatures?

The MM3Z56VB is characterized for operation from −65 °C to +150 °C junction temperature, with Zener voltage exhibiting predictable positive temperature coefficient behavior typical of higher-voltage Zeners. At 125 °C, V_Z shifts approximately +0.08%/°C relative to 25 °C, resulting in ~+0.8 V increase. This drift is documented in onsemi's typical performance curves and must be accounted for in high-temperature reference designs using the MM3Z56VB.

Is the MM3Z56VB RoHS compliant and lead-free?

Yes, the MM3Z56VB features matte tin (Sn) finish and is fully RoHS compliant and lead-free, meeting EU Directive 2011/65/EU and JESD204 standards. The SOD−323FL package uses Pb-free molding compound and terminations, verified through onsemi's material declarations and third-party testing. This compliance ensures the MM3Z56VB is suitable for global commercial and industrial markets without restriction.