Zener single diode is a maximum voltage (Tol) that can be supplied at 10%.As part of the operation, the maximum voltage - Zener (Nom) is reduced to 2.2V.Setting the working test voltage to 5mA will allow this device to operate.
1N3477 Features
the working test voltage to 5mA minimal dynamic impedance is 5mA
1N3477 Applications
There are a lot of Microsemi Corporation 1N3477 applications of zener single diodes.