ISIS: a fail-safe interface realised in smart power technology

ISBN: 0769506461Actuators of safety critical systems must be driven by fail-safe signals. Under a failure in the system such a signal has to be either on the correct state or on the safe state. This paper describes a fail-safe interface able to generate the fail-safe signals required in this context. The circuit is realised in a smart-power technology allowing one to deliver fail-safe signals having the power characteristics required in a railway system. It can replace traditional fail-safe interfaces realised by means of bulky and expensive discrete components

Design of a self-checking microprocessor for real-time application

International audienc

Synthesis and Properties of Polymeric Schiff-Bases and Their CO(II), CU(II) and NI(II) Complexes

Soluble and insoluble polymeric Schiff bases PolySalPn and PolySal-DPT* have been synthesised. The polymers and their copper(II), nickel(II) and cobalt(II) complexes have been fully characterised by their elemental analyses and by spectroscopic methods. The Co—PolySalDPT proved to be as efficient as the corresponding monomeric complex in catalysing the oxidation of 2,6-di-t-butylphenol

Design of a self-checking microprocessor for real-time applications

ISBN: 0080334385Concerns the design of a microprocessor dedicated to safety applications and more particularly to automatic train control. This microprocessor is self-checking i.e. able to detect its own errors. Its name is COBRA (controller with built-in selfchecking for real-time applications). In the design of this circuit, low-level fault hypotheses for the N-MOS technology are considered. In this case redundant faults, i.e. undetectable faults, generally exist in any design and thus fault detecting capabilities must be provided for sequences of faults. The functional circuits will process with coded data and will be checked by strongly code-disjoint checkers. COBRA's data path processes independently 19 different signals, and supervises 14 level inputs (binary values). 7 independent outputs could be binary values, and 3 could be clocks. The data path communicates with an external PROM, used as program storage for COBRA. This PROM is addressed with 14 bits, multiplexed over the 8-bit address/data internal bus of the data path. It also contains one serial I/O, a 64 byte RAM, and 3 independent 14 bits counters. An 8 bit ALU could be used for arithmetical or logical operations. A set of 42 instructions processes all these operations