STMicroelectronics

SMM4F18A-TR

SMM4F18A-TR Description

The SMM4F18A-TR from STMicroelectronics is a unidirectional Zener-type TVS diode designed for general-purpose transient voltage suppression in electronic circuits. Part of the SMM4F, TRANSIL™ series, it features an 18V reverse standoff voltage (V_RWM) and a minimum breakdown voltage (V_BR) of 20.9V, ensuring robust protection against voltage spikes. With a peak pulse power rating of 400W and a clamping voltage (V_C) of 39.3V at peak pulse current (I_PP), it effectively safeguards sensitive components from transient events like ESD, lightning surges, and inductive load switching. Packaged in a DO-222AA (SMB) surface-mount form factor, it is optimized for high-density PCB designs and complies with ROHS3 and REACH environmental standards.

SMM4F18A-TR Features

• High Surge Handling: Supports 59A peak pulse current (8/20µs waveform), ideal for harsh electrical environments.
• Low Clamping Voltage: 39.3V max ensures minimal stress on downstream components during transients.
• Reliable Performance: Unidirectional operation with 20.9V min breakdown voltage for precise protection thresholds.
• Compact & Robust: Surface-mount SMB package (Tape & Reel) enables automated assembly and space-efficient layouts.
• Compliance: ROHS3, REACH, and EAR99 certified, suitable for global industrial applications.
• Wide Operating Range: MSL 1 (unlimited shelf life) and general-purpose compatibility enhance versatility.

SMM4F18A-TR Applications

• Industrial Electronics: Protects PLCs, sensors, and control systems from voltage transients.
• Automotive Systems: Safeguards CAN bus, infotainment, and power supply lines against load-dump surges.
• Consumer Devices: Used in smartphones, routers, and USB ports for ESD protection (IEC 61000-4-2).
• Power Supplies: Mitigates switching surges in AC/DC converters and DC-DC modules.
• Telecom Infrastructure: Shields base stations and networking equipment from lightning-induced surges.

Conclusion of SMM4F18A-TR

The SMM4F18A-TR combines high-energy transient suppression, low clamping voltage, and compact packaging to deliver superior circuit protection. Its unidirectional design and 400W peak power rating make it a standout choice for industrial, automotive, and consumer applications where reliability and space constraints are critical. STMicroelectronics' rigorous quality standards ensure consistent performance, making this TVS diode a cost-effective solution for mitigating voltage transients in modern electronics.