An electrical device like this requires a reverse leakage current of 200nA @ 23V.While the device is operating, the maximum voltage - Zener (Nom) is reduced to 27.69V.
MTZJ30SA R0G Features
reverse leakage current of 200nA @ 23V 200nA @ 23V is the maximum voltage (Tol)
MTZJ30SA R0G Applications
There are a lot of Taiwan Semiconductor Corporation MTZJ30SA R0G applications of zener single diodes.