onsemi MM3Z39VT1

Overview

MM3Z39VT1 from onsemi is a 39 V, 200 mW surface-mount Zener diode in SOD−323 package, designed for precision voltage regulation and overvoltage protection in space-constrained circuits. It delivers nominal Zener voltage of 39 V at 2 mA test current, with dynamic impedance of 130 Ω at IZT and leakage current ≤0.05 µA at 27.3 V reverse bias - used in voltage reference and ESD-protected signal conditioning stages.

For engineers reviewing the MM3Z39VT1 datasheet, pinout, applications, or equivalent options, key selection criteria include its 39 V nominal Zener voltage tolerance (±5.1%), low 45 pF capacitance at 0 V, −2.5 mV/°C temperature coefficient, and Pb-free SOD−323 footprint compatibility with high-density portable electronics layouts.

Technical Context

The MM3Z39VT1 operates as a two-terminal voltage reference device relying on controlled reverse-breakdown conduction. Its Zener voltage is specified at 2 mA (IZT), with guaranteed min/max values of 37 V and 41 V, and exhibits a negative temperature coefficient of −2.5 mV/°C - indicating decreasing breakdown voltage with rising junction temperature.

It features 200 mW steady-state power dissipation on FR-5 board at 25°C, derating linearly at 1.5 mW/°C above ambient, and achieves thermal resistance of 635°C/W junction-to-ambient. The device meets Class 3 ESD rating (>16 kV HBM) and UL 94 V−0 flammability compliance.

Key Specifications

Pinout & Package

SOD−323 surface-mount package: 1.7 mm × 1.25 mm body, 0.9 mm height, cathode marked by band. Two-terminal device with polarity-sensitive mounting.

Key Features

Applications

Equivalent & Alternatives

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

Compared with BZX384-B39,115 and MMSZ4702T1G, the MM3Z39VT1 offers the smallest footprint (SOD−323), lowest capacitance (45 pF), and tightest integration for space-critical portable designs - at the trade-off of lower power rating and higher dynamic impedance.

Availability

MM3Z39VT1 is available at Aetrix Electronics and suitable for battery management systems, USB interface protection, industrial sensor modules, and IoT edge node power regulation requiring stable component supply and RoHS-compliant sourcing.

Supply support for MM3Z39VT1 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 focused on energy-efficient electronics, delivering silicon solutions for automotive, industrial, cloud, and intelligent power systems.

The MM3Z series is part of onsemi's precision Zener voltage regulator portfolio, engineered specifically for miniaturized, high-reliability voltage reference and overvoltage protection in portable and space-constrained applications.

FAQ

What is the nominal Zener voltage and tolerance of MM3Z39VT1?

The MM3Z39VT1 has a nominal Zener voltage of 39 V with a guaranteed range of 37 V to 41 V at 2 mA test current (IZT), corresponding to ±5.1% tolerance. This specification is validated per the onsemi datasheet Rev. 7 and applies strictly at TA = 25°C with pulse testing to avoid self-heating effects. The MM3Z39VT1 maintains this voltage accuracy across its rated operating temperature range when used within thermal derating limits.

Does MM3Z39VT1 support lead-free soldering processes?

Yes, the MM3Z39VT1 is offered in a Pb-free SOD−323 package (indicated by the "G" suffix), with leads plated in pure tin. It supports standard lead-free reflow profiles, including peak temperatures up to 260°C for 10 seconds, as confirmed in the mechanical characteristics section of the official datasheet. The MM3Z39VT1 complies with JEDEC J-STD-020 moisture sensitivity level (MSL) requirements for surface-mount assembly.

What is the maximum reverse leakage current for MM3Z39VT1 and at what voltage is it specified?

The MM3Z39VT1 exhibits a maximum reverse leakage current of 0.05 µA at VR = 27.3 V, as specified in the Electrical Characteristics table. This value is measured at TA = 25°C and reflects the device's ability to maintain high-impedance blocking behavior well below its nominal Zener voltage. The low leakage directly contributes to minimal standby power loss in MM3Z39VT1-based reference dividers and bias networks.

How does the temperature coefficient of MM3Z39VT1 affect its voltage stability?

The MM3Z39VT1 has a temperature coefficient of −2.5 mV/°C, meaning its Zener voltage decreases by 2.5 mV for every 1°C rise in junction temperature. This negative coefficient is typical for Zeners in the 30–50 V range and must be factored into precision reference designs. For example, over a −40°C to +85°C ambient range, the MM3Z39VT1's voltage shift is approximately ±313 mV - a key parameter accounted for in MM3Z39VT1-based sensor calibration algorithms.

Can MM3Z39VT1 be used as a substitute for higher-power Zener diodes in low-current applications?

Yes, the MM3Z39VT1 can replace higher-power Zeners such as the MMSZ4702T1G in applications drawing ≤2 mA bias current, provided the 200 mW power limit and SOD−323 footprint are acceptable. Its 39 V regulation, low 45 pF capacitance, and Class 3 ESD rating make it especially suitable for signal-level clamping where thermal mass is limited. However, the MM3Z39VT1 is not a drop-in replacement due to different package dimensions and thermal characteristics.