The MMBZ5239BLT1G is part of ON Semiconductor's Zener Diode family. It is a 9.1V zener diode with a power dissipation capability of 225mW. It is a 2-pin surface mount device (SMD) made of silicon, it is temperature compensated and is designed for low power/voltage regulation applications. It features very low leakage current capabilities, making it a popular choice for general purpose protection and clamping applications. It has a lead-free, RoHS compliant design and its small size makes it ideal for high density circuit board assemblies. It is typically used for microprocessor, microcontroller, and logic voltage regulation, and also in simple voltage regulation circuits.