An analogue subthreshold fuzzy logic controller [for smart sensors]

Fuzzy logic systems have been used both to control non-linear systems, and for applications requiring inference, and are therefore an attractive proposition for the information processing function. The extremely low power consumption requirement is met by designing analogue circuits which operate in the subthreshold region, where the currents flowing are typically of the order of nano-amps or less. We use floating-gate devices as non-volatile analogue memories, thereby avoiding the power consumption associated with refreshable analogue memories and the accompanying digital non-volatile memories and D/A converters