In this paper, we proposed the designing of control system for cantilever based biosensor. In cantilever based biosensor, as the device dimension changes the sensitivity of the device reduces which is of prime important in biosensor. To improve the sensitivity of the device we propose to fabricate the digital feedback control system which will take care of providing the predeflection of the cantilever beam to maintain the constant gap between the electrodes inspite of variation due to fabrication process. We have design digital feedback control system for biosensor. The stability and related issues of the proposed device is discussed.

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Biosensor Microcantilever Feedback system FPGA