An electrical current smart transducer based on PSoC platform and integrated spin-valve sensor with embedded thin film Ruthenium temperature sensor

This work presents an intelligent electrical current sensor that combines a programmable system on chip (PSoC) with a microfabrication of a giant magnetoresistance sensor (GMR) and resistive temperature detector (RTD). Four spin-valve GMR elements configured in a Wheatstone bridge sense the electrical current, while a thin film RTD based on Ruthenium measures the temperature for spin-valve bridge sensitivity thermal compensation. The mixed signal PSoC allows implement in a single chip all electronic circuits needed to design a smart transducer: the spin-valve biasing, conditioning signal, analog to digital converter, digital signal processing and ports for communications. In the experimental results a small thermal study of the spin-valve is reported. The smart transducer digital output is characterized in the range of ±10 A in dc regime as well as 50 Hz ac regime up to 10 A peak.