An electrical device like this requires a reverse leakage current of 100μA @ 1V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 2.5V.For operation, diode reaches 1.2V @ 200mA at the maximum voltage - Forward (Vf).
1N5222B_T50A Features
reverse leakage current of 100μA @ 1V 100μA @ 1V is the maximum voltage (Tol)
1N5222B_T50A Applications
There are a lot of ON Semiconductor 1N5222B_T50A applications of zener single diodes.