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Thermal Indicators Using Chemical Cholesterol Compounds

IP.com Disclosure Number: IPCOM000062896D
Original Publication Date: 1985-Jan-01
Included in the Prior Art Database: 2005-Feb-18

Publishing Venue

IBM

Related People

Authors:
Boone, LE Pavlik, J [+details]

Abstract

Chemical cholesterol compounds can be applied to electronic devices, such as thermal conduction modules (TCMs), as an indication of quiescence in systems that can be partially powered down. An inexpensive, reliable method of determining the power condition of each TCM is needed to prevent inadvertent "hot-plugging" of a TCM. Current proposals are for positive mechanical/electrical interlocks or redundant electrical indicator lamps. Both proposals defeat the purpose of the design to totally remove electrical power from the affected TCM location. Chemical cholesterol compounds are commercially known as temperature-sensitive liquid crystals. Liquid crystal material can be applied to the TCM by one of two methods, either direct application, similar to painting, or by an adhesive-backed film.