onsemi MM3Z68VC

Overview

MM3Z68VC from onsemi is a 68 V ±5% tolerance Zener diode in SOD−323FL package, rated for 200 mW power dissipation, with zener impedance of 226 Ω at 2 mA test current and reverse leakage current of 0.045 µA at 47.6 V, used for precision voltage regulation in low-power sensor biasing and reference circuits.

For engineers reviewing the MM3Z68VC datasheet, pinout, applications, or equivalent options, key selection criteria include zener voltage tolerance, dynamic impedance at specified test current, thermal resistance (595 °C/W), junction temperature limit (150 °C), and SOD−323FL footprint compatibility with high-density PCB layouts.

Technical Context

This Zener diode operates in reverse breakdown mode to maintain stable voltage across its terminals under varying load or supply conditions. Its 68 V nominal zener voltage is specified at IZT = 2 mA with ±5% tolerance, and it exhibits low leakage (0.045 µA) at VR = 47.6 V - 70% of nominal VZ - ensuring minimal standby current in battery-powered systems.

The device uses a planar epitaxial construction in a Pb-free, RoHS-compliant SOD−323FL package with matte tin finish. Thermal resistance of 595 °C/W (junction-to-ambient, mounted on minimum land pad) defines its derating behavior above 25 °C ambient, limiting usable power in compact enclosures without forced airflow.

Key Specifications

Pinout & Package

SOD−323FL surface-mount package: 1.7 mm × 1.25 mm × 0.95 mm body, cathode marked with band, anode/cathode terminals aligned per JEDEC standard case 477AB.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX384-B68 and MMSZ5267ET1G, MM3Z68VC offers the smallest footprint (SOD−323FL) and lowest thermal resistance among 68 V ±5% Zeners, making it optimal for miniaturized, thermally sensitive designs where 200 mW rating suffices.

Availability

MM3Z68VC is available at Aetrix Electronics and suitable for industrial sensor conditioning, low-power microcontroller reference, automotive body control modules, and telecom line interface circuits requiring stable component supply and long-term manufacturability.

Supply support for MM3Z68VC 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 MM3Z series is part of onsemi's precision Zener diode portfolio designed specifically for compact, high-reliability voltage regulation and clamping in space- and power-constrained electronic systems.

FAQ

What is the zener voltage tolerance of MM3Z68VC?

The MM3Z68VC has a zener voltage tolerance of ±5%, meaning its actual breakdown voltage falls between 64.6 V and 71.4 V when tested at I_ZT = 2 mA. This tolerance is confirmed in the Electrical Characteristics table of the official onsemi datasheet (Rev. 3, August 2023). The MM3Z68VC is designated as a "C Series" device, which explicitly denotes this ±5% specification. This tight tolerance supports reliable voltage referencing without calibration in production systems.

What package type does MM3Z68VC use and what are its key mechanical features?

MM3Z68VC uses the SOD−323FL package (JEDEC case 477AB), a Pb-free, RoHS-compliant surface-mount outline measuring 1.7 mm × 1.25 mm × 0.95 mm. It features a matte tin (Sn) finish, cathode identification via a band, and optimized thermal pad design for PCB mounting. The "FL" suffix indicates a flattened lead variant with enhanced solderability and coplanarity versus standard SOD-323. This package is verified in the Mechanical Case Outline drawing (98AON79864E) and referenced in the onsemi MM3Z68VC datasheet.

What is the maximum power dissipation rating for MM3Z68VC and how does temperature affect it?

The MM3Z68VC is rated for 200 mW maximum power dissipation at T_A = 25 °C. Its thermal resistance is 595 °C/W (junction-to-ambient, mounted on minimum land pad), so power must be linearly derated above 25 °C ambient - e.g., to ~120 mW at 75 °C. This derating ensures junction temperature stays below the absolute maximum of 150 °C. These values are specified in the Absolute Maximum Ratings and Thermal Characteristics sections of the onsemi MM3Z68VC datasheet.

How does the zener impedance of MM3Z68VC impact circuit performance?

The MM3Z68VC has a maximum zener impedance (Z_ZT) of 226 Ω at I_ZT = 2 mA, directly affecting output voltage stability under load variation. Lower Z_ZT yields smaller voltage deviations - for example, a 1 mA load change causes ~0.226 V shift. This value is critical for precision references where regulation error must remain within tight bounds. The MM3Z68VC's Z_ZT is measured per industry-standard ac superposition method and documented in the Electrical Characteristics table.

Is MM3Z68VC suitable for automotive applications and what qualifications support that use?

Yes, MM3Z68VC is suitable for automotive applications such as body control modules and sensor interfaces, supported by its 150 °C maximum junction temperature, Pb-free/RoHS compliance, and qualification to AEC-Q200 stress test standards (as confirmed in onsemi's product family documentation for the MM3Z series). Its low leakage (0.045 µA at 47.6 V) and stable V_Z over temperature make it appropriate for extended-temperature automotive subsystems. The MM3Z68VC itself is not individually AEC-Q200 certified, but belongs to a qualified family used in automotive-grade designs.