MIL-PRF-19500-486 Coupler, Opto Electronic, Semiconductor Device, Solid State, Types 4N22, 4N22A, 4N23, 4N23A, 4N24, 4N24A, 4N22U, 4N23U, And 4N24U, Jan, Jantx, Jantxv, And JansThis specification covers the performance requirements for solid state optically coupled isolators in which a gallium aluminum arsenide diode light source is optically coupled to a silicon NPN phototransistor. Four levels of product assurance are provided for each type as specified in MIL-PRF-19500.