Programmable logic devices with spare circuits for replacement of defects

摘要

A programmable, integrated circuit, logic array device has several regular logic groups and at least one spare logic group. If any of the regular logic groups is defective, the spare logic group is used to make up for the defective logic group. To accomplish this, programming and data input signals that would normally go to the defective logic group are redirected to another logic group. The data output signals of the other group are substituted for the data output signals of the logic group that would normally have received the programming and data input signals that were redirected to the other logic group.