onsemi MMBZ9V1ALT1

Overview

MMBZ9V1ALT1 from onsemi is a dual common-anode Zener diode array in SOT-23 package, designed for transient voltage suppression and ESD protection of two independent signal lines. It features 9.1 V nominal Zener breakdown voltage (±5%), 24 W peak pulse power at 1.0 ms, clamping voltage of 14 V at 1.7 A peak pulse current, and IEC 61000-4-2 Level 4 ±30 kV contact discharge rating. It is used in USB, HDMI, and low-voltage I/O port protection in consumer electronics.

For engineers reviewing the MMBZ9V1ALT1 datasheet, pinout, applications, or equivalent options, key selection criteria include unidirectional clamping performance, dual-line protection density, SOT-23 footprint compatibility, and compliance with Class 3B HBM (>16 kV) and IEC 61000-4-2 Level 4 ESD standards.

Technical Context

This device integrates two monolithic Zener junctions sharing a common anode (Pin 3), enabling independent reverse-biased clamping on Pins 1 and 2. Its 9.1 V nominal breakdown is specified at 1 mA test current with ±5% tolerance and +7.5 mV/°C temperature coefficient.

The 24 W non-repetitive peak power rating applies to the 10/1000 µs waveform per Figure 6; derating begins above 25 °C ambient per Figure 7. Thermal resistance is 556 °C/W on FR-5 board, limiting steady-state dissipation to 225 mW at 25 °C.

Key Specifications

Pinout & Package

SOT-23 package (Case 318, Style 12) with gull-wing leads; void-free thermosetting plastic case rated UL 94 V-0; Pb-free and RoHS compliant.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-Zener ESD protection applications.

Compared with MMBZ9V1ALT1, MMBZ9V1ALT1G offers identical protection performance with enhanced RoHS labeling, while SZMMBZ9V1ALT1G adds automotive qualification at higher cost and longer lead time - select based on end-equipment regulatory scope, not electrical need.

Availability

MMBZ9V1ALT1 is available at Aetrix Electronics and suitable for USB interface protection, HDMI hot-plug circuitry, and industrial sensor front-ends requiring stable component supply and consistent SOT-23 footprint availability.

Supply support for MMBZ9V1ALT1 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 supplier of energy-efficient semiconductor solutions, headquartered in Phoenix, Arizona, with manufacturing and design centers worldwide.

The MMBZxxxALT1G series belongs to onsemi's transient voltage suppression portfolio, engineered specifically for high-density, low-capacitance ESD protection in space-constrained consumer, computing, and medical electronics.

FAQ

What is the Zener breakdown voltage tolerance for MMBZ9V1ALT1?

The MMBZ9V1ALT1 has a nominal Zener breakdown voltage of 9.1 V with a ±5% tolerance, meaning the actual V_BR falls between 8.65 V and 9.56 V when measured at 1 mA test current and 25 °C ambient. This tolerance is confirmed in the Electrical Characteristics table on page 3 of the official onsemi datasheet (Rev. 22, June 2026). The MMBZ9V1ALT1 maintains this specification across its qualified operating temperature range.

Does MMBZ9V1ALT1 support bidirectional ESD protection?

Yes, the MMBZ9V1ALT1 supports bidirectional protection through external circuit configuration: connecting Pin 1 and Pin 2 to separate signal lines and grounding Pin 3 enables symmetrical clamping for both positive and negative transients. While the device itself is unidirectional per junction, the common-anode topology allows implementation as a bidirectional protector - verified in Figure 6 and Typical Common Anode Applications (page 6) of the onsemi datasheet for MMBZ9V1ALT1.

What is the maximum clamping voltage of MMBZ9V1ALT1 under ESD stress?

The MMBZ9V1ALT1 exhibits a maximum clamping voltage (V_C) of 14 V when subjected to its rated peak pulse current of 1.7 A, as defined by the 10/1000 µs waveform in Figure 6 of the onsemi datasheet. This value is guaranteed across the full operating temperature range and forms the basis for system-level overvoltage margining in designs using MMBZ9V1ALT1 for I/O protection.

Is MMBZ9V1ALT1 RoHS compliant and halogen-free?

Yes, MMBZ9V1ALT1 is RoHS compliant and Pb-free, as explicitly stated in the Features section of the onsemi datasheet: "These Devices are Pb−Free and are RoHS Compliant." The device carries no halogenated flame retardants and meets UL 94 V-0 flammability rating. The "T1" suffix aligns with onsemi's Pb-free packaging standard, and full compliance documentation is available via onsemi's quality portal for MMBZ9V1ALT1.

Can MMBZ9V1ALT1 replace MMBZ9V1ALT1G in existing designs?

Yes, MMBZ9V1ALT1 can directly replace MMBZ9V1ALT1G in most applications because both share identical electrical specifications, thermal characteristics, SOT-23 mechanical outline, and pinout. The "G" suffix indicates explicit Pb-free marking per onsemi's packaging convention but does not reflect any die or performance change. Designers may substitute MMBZ9V1ALT1 for MMBZ9V1ALT1G without layout or validation impact, provided RoHS labeling requirements are reviewed for final product certification.