The MMBZ5231BLT1G with ON Semiconductor Zener Diodes 5.1V 225mW is a voltage regulator diode manufactured by ON Semiconductor. This device is designed for use in low noise, low power circuits, and provides a stable voltage regulation. The diode has a 5.1V zener voltage and a maximum power dissipation of 225 milliwatts. It is housed in a small SOT23 package and features an excellent ESD rating, making it suitable for use in many applications. Additionally, its low forward voltage drop and low leakage current enable it to reduce power losses in high efficiency voltage regulation circuits.