Use of PSoC/sup /spl trade// component in a frequency based acquisition method for smart sensors applications

This work presents the development of a useful frequency based acquisition system, based on a programmable system on chip developed by Cypress/sup /spl trade// MicroSystems. The goal is to demonstrate the possibilities offered by system-on-chip programmable devices in specific processing systems, where the costs make the use of specific integrated circuits unaffordable. PSoC circuits built by Cypress Microsystems includes all the components necessary to built classical acquisition circuits based-on-ADC as, also, to include actual and powerful frequency-based acquisition circuitry inside the component. This opportunity is exploited in the paper in order to compare both data acquisition methodologies. Moreover, the frequency-based data acquisition method implemented in the circuit is based on a voltage to frequency-code converter and uses the indirect count methodology. This conversion method produces a very versatile, precise and scalable structure for data acquisition. Also, it has been demonstrated that the powerful Cypress/sup /spl trade// Programmable System on Chip (PSoC/sup /spl trade//) platform, results in a perfect way to acquire, condition, multiplex, process and transmit external analogue data to different external processors, liberating the main processor of tedious works while allowing the system to spend time on processing instead of capturing data.