Patent ID: 7608978
Filing Date: 2009-10-27
Classification: G01N,H01L

Abstract:
1. A sensing system including a detector and an oscillating circuit comprising a coupling device, an amplifier, and a plurality of resonators, wherein: each resonator comprises: wherein for each resonator, when the input electrode assembly is activated, the input electrode assembly and the output electrode assembly cooperate to produce a frequency response representative of one of presence or absence of a sufficient quantity of the stimulus; wherein the resonators are coupled in series from 1 to n; and wherein: the n th resonator has an output connected to an amplifier input of the amplifier; the amplifier has an amplifier output connected to a coupling device input of the coupling device; the coupling device has a first coupling device output connected to an input of the first resonator; the coupling device has a second coupling device output connected to the detector; and the amplifier has a gain that is insufficient to cause the oscillator circuit to meet Barkhausen criteria when at least one of the n resonators produces a frequency response representative of absence of a sufficient quantity of its respective stimulus and that is sufficient to cause the oscillator circuit to meet Barkhausen criteria when all of the n resonators produce a frequency response representative of presence of a sufficient quantity of their respective stimulus, so that the detector emits a detection signal only when all of the n resonators produce a frequency response representative of presence of a sufficient quantity of their respective stimulus.