External Control Signals Research Articles

Adaptable Large-Scale-Integrated Military and Space Systems

The advent of low-cost microelectronics and of large-scale integration (LSI) in particular has made it practical to design adaptable circuits and systems to achieve various significant objectives. The two objectives discussed in this paper are the design and technology of Microelectronic Multifunction Circuit Blocks to specifically simplify the logistics support problem of large, long-life military systems and the use of Dynamically Redundant Microelectronic Circuit Blocks to mechanize efficient self-repair systems. Presently practical adaptation techniques involve reversible and irresversible electronic modification of the interconnection pattern which is super-imposed on a matrix of components or of logic or analog circuits. Future possibilities include changes in the component characteristics themselves. Among the various design and technological approaches to adaptable multifunction microcircuits the Pin-Programmable Adaptable Microcircuits are recognized as the most versatile. This adaptation scheme is then extended to include dynamically redundant microcircuits. The basic principle of dynamic redundancy is that the interconnection paths between the redundant circuit blocks are not fixed but can be varied by external control signals. This adaptation is accomplished by switches placed around distribution points in the interconnection pattern. The switches are opened and closed by a logic control network programmed by an Equipment Redundacny Programme. Each circuit can operate in various Redundancy Modes depending on the state of the switches around it. The basic terms are defined and the advantages of dynamic redundancy are listed.