SZMMBZ6V8ALT1G

Overview

The SZMMBZ6V8ALT1G is a dual monolithic silicon Zener diode in an SOT-23 package, designed for transient overvoltage and ESD protection. It features a common anode configuration to protect two separate lines within one component. The device operates within a junction temperature range of -55°C to +150°C. Key electrical parameters include a nominal breakdown voltage of 6.8 V with a tolerance of ±5%, a maximum working peak reverse voltage of 4.5 V, and a maximum reverse leakage current of 0.5 µA at VRWM. It supports a peak power dissipation of 24 W for a 1.0 ms pulse duration and offers an ESD rating of Class 3B (>16 kV) per the Human Body Model.

Feature Summary

• Dual common anode design enables bidirectional or unidirectional configurations for protecting two independent signal lines using a single surface-mount package.
• Automotive-grade qualification (AEC-Q101) with PPAP capability, indicated by the SZ prefix for applications requiring unique site control.
• High ESD protection performance meeting IEC61000-4-2 Level 4 standards with ±30 kV contact discharge immunity.

Applications

• Protection of data and address buses in computers and business machines
• ESD suppression on communication system interfaces
• Transient voltage protection for medical equipment input/output lines

Procurement Notes

Verify the specific ordering suffix to confirm packaging quantity; T1 indicates a 3,000-unit tape and reel, while T3 denotes a 10,000-unit reel. Confirm that the SZ prefix is required for automotive projects necessitating PPAP documentation and specific manufacturing site controls. Ensure compliance with RoHS directives and lead-free specifications during procurement validation.

Selection Notes

Select this component when board space is limited and dual-line protection is required from a single footprint. Choose the SZ variant specifically for automotive assemblies demanding AEC-Q101 qualification. Verify that the 6.8 V breakdown voltage aligns with the target circuit's operating voltage and that the 24 W peak power rating suffices for the expected transient energy levels.

Part Context

This part belongs to the MMBZxxxALT1G series of dual common anode Zener diodes manufactured by onsemi. The series utilizes a standard SOT-23 (CASE 318) plastic package optimized for automated assembly. The SZ prefix differentiates automotive-grade units from standard commercial versions, ensuring traceability and adherence to stricter quality management systems.

Replacement Considerations

Direct functional equivalents within the same series include MMBZ6V8ALT1G for commercial use. For automotive replacements requiring identical qualification, verify availability of other SZ-prefixed devices with matching breakdown voltages. Cross-referencing pinout compatibility is essential as the common anode configuration must be maintained in the new component.

FAQ

How does the common anode configuration function electrically?

The device contains two independent Zener junctions sharing a common anode terminal (Pin 3). This allows Cathode 1 (Pin 1) and Cathode 2 (Pin 2) to independently clamp voltage spikes on two separate lines relative to the common ground/anode reference.

What is the difference between the MMBZ and SZ prefixes?

The SZ prefix indicates that the device is qualified to AEC-Q101 standards and is PPAP capable, intended for automotive and high-reliability applications requiring unique site identification and change control. Standard MMBZ parts are for general commercial use.

What is the maximum clamping voltage for this device?

According to the datasheet, the maximum clamping voltage (VC) at the peak pulse current (IPP) of 2.5 A is 9.6 V.