In this paper, we report on the design, fabrication and testing of a passive pressure transensor. The sensor uses the self-resonant frequency modulation of an integrated coil to detect the pressure variations. This modulation is generated by the displacement of a ferrite core attached to a silicone rubber membrane relative to the coil. This scheme simplifies the packaging of the passive transensor by removing the requirement for a separate capacitor to form the resonator. A 1.37μH coil having a dimension of 3mm×3mm and 30 turns is used in a prototype design yielding a sensitivity of 34.7 kHz/kPa with a cylindrical ferrite core of 9.5mm diameter and 0.5mm height.
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