An electrical device like this requires a reverse leakage current of 3μA @ 2V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 4.7V.For operation, diode reaches 1.1V @ 200mA at the maximum voltage - Forward (Vf).
BZV55C4V7 Features
reverse leakage current of 3μA @ 2V 3μA @ 2V is the maximum voltage (Tol)
BZV55C4V7 Applications
There are a lot of Microsemi Corporation BZV55C4V7 applications of zener single diodes.