An electrical device such as this requires reverse leakage current of 100nA @ 43V.During operation, the maximum voltage - Zener (Nom) is reduced to 56V volts.
ACZRM5263B-HF Features
reverse leakage current of 100nA @ 43V 100nA @ 43V is the maximum voltage (Tol)
ACZRM5263B-HF Applications
There are a lot of Comchip Technology ACZRM5263B-HF applications of zener single diodes.