MAGFET with embedded Gilbert gain cell

A modified Gilbert gain cell implemented with lateral-PNP transistors has been successfully used to amplify the output current signal from an N-channel split-drain MOS transistor, or MAGFET. Compared with other previously reported signal conditioning circuits for MAGFETs, the herein presented approach adds the advantage of featuring programmability for the current gain, thus providing means of controlling the sensitivity of the magnetic detecting device. Measurements of prototypes of the circuit, fabricated in 0.35mum CMOS, have proved the concept.