An electrical device like this requires a reverse leakage current of 100nA @ 15V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 20V.For operation, diode reaches 900mV @ 10mA at the maximum voltage - Forward (Vf).
MMSZ5250ET1 Features
reverse leakage current of 100nA @ 15V 100nA @ 15V is the maximum voltage (Tol)
MMSZ5250ET1 Applications
There are a lot of Rochester Electronics, LLC MMSZ5250ET1 applications of zener single diodes.