Smiths Industries Public Limited Company

Dowty and Smiths Industries Controls Limited

Edward S Eccles

James C Green

Arthur F Saunders

An electronic assembly has a substrate with several conductive tracks and with a switching matrix within the thickness of the substrate. Several groups of identical integrated circuits are mounted on the substrate, one circuit from each group being operatively connected into the assembly by the switching matrix. A processor detects malfunction of a circuit and controls the switching matrix to disconnect that circuit and operatively connect into the assembly an alternative circuit from the same group.

Electronic circuit assembly an a substrate containing programmable

An integrated circuit substrate is made by exposing a mask to a composite representation of the pattern of integration of several different dice. The mask is exposed several times to produce several composite representations on the mask. Several different composite representations may be formed on the same mask. Identical aligned composite representations are checked by optically comparing corresponding dice in different composite representations via respective optical systems. The several composite representations on the mask are transferred simultaneously to the substrate to reproduce the pattern of integration of the dice at a plurality of locations in the substrate. The area of the mask covered by the composite representations may be greater than the usable area of the substrate such that for at least two of the composite representations only a portion of the composite representations is reproduced on the substrate, some of those dice not reproduced in one of the composite representations being reproduced in the other of the two composite representations. One half of the mask may have composite representations relating to one processing step, while the other half of the mask relates to a different processing step, the mask being reoriented after the first step so that the part of the substrate exposed initially to the one half of the mask is subsequently exposed to the other half of the mask, the other part of the substrate being rejected.

Intergrated circuit substrates

A control system for a gas-turbine engine has two parallel control units, either one of which can be switched to supply control signals to the engine in response to input signals, such as from the pilot's control lever and from various sensors. Each unit has a limiter that limits the fuel supply to the engine if the engine speed approaches or exceeds a predetermined maximum. A monitor unit in each control unit detects when the limiter has assumed control of the engine for more than a predetermined time, and switches the system to control by the other control unit. The predetermined engine speed may be different for different settings of the pilot's control lever. The monitor unit in such an arrangement, may receive signals in respect of the acceleration and deceleration of the engine and switch to the other control unit only when the speed is outside the predetermined speed for the pilot lever setting, and when the acceleration or deceleration is not such as to bring the speed back within the predetermined speed.

Growing community of inventors

Bishop's Cleeve, United Kingdom

Edward S Eccles