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Grade of written test: Final grade: Grade of project: Signature: Technologies for Sensors and Clinical Instrumentation 5 February 2016 FAMILY NAME ………………………… NAME ………………………. MATR ………… PREFERENCES FOR ORAL: † 15/2 (h.10) † 16/2 (h.10) † next calls Notes: - Answers are considered complete only if units of measurement are indicated. - Only answers on printed sheets are considered for evaluation. Q. 1) (5 points) A given physical property X, that can vary from ൌ0 to ൌ1 0 , is measured by a linear resistive sensor in a way that its resistance is 1000 Ω when ൌ0 and 1100 Ω when ൌ1 0. The sensor is conditioned with a resistive bridge in “quarter bridge” modality, with a power supply ܸ௥, that allows to limit the maximal dissipated power of the sensor to 25 mW. The conditioned analog signal is sampled by an A/D converter having an input range 0-10 V. …/2 - 1.a) Assume that the bridge is balanced for ܺൌ0 and that the values of the other resistances of the bridge provide that maximal possible sensitivity. Draw the conditioning circuit with the amplifier stage. Calculate the maximum relative error of non-linearity of the bridge both in terms of X, and in terms of voltage. ………………………………………….. ………………………………………….. ………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. ……………………………………………………………………………………………………….. …/1.5 - 1.b) Determine the minimum value of balancing factor…