An electrical device like this requires a reverse leakage current of 5μA @ 1V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 3.3V.For operation, diode reaches 1.4V @ 1A at the maximum voltage - Forward (Vf).
JANS1N6312C Features
reverse leakage current of 5μA @ 1V 5μA @ 1V is the maximum voltage (Tol)
JANS1N6312C Applications
There are a lot of Microsemi Corporation JANS1N6312C applications of zener single diodes.