FIELD: electronic engineering; protection of integrated-circuit information against keying. SUBSTANCE: novelty is that protected-information circuit is closed with shielding surface carrying network with plurality of nodes. Some nodes are coupled with means for comparing desired and actual values. Each node is checked with aid of these means for characteristic output current. Deviations from characteristic output current cause variations in information stored in circuit and protected against keying or analysis. EFFECT: enhanced reliability of protective means. 9 cl, 1 dwg
