Design of a CMOS oscillator with magnetic-field frequency modulation

A magnetosensitive n-channel split-drain MOSFET (MAGFET) integrated with a current-controlled oscillator on a single chip is described. This magnetically controlled oscillator (MCO), which was fabricated in 5-/spl mu/m CMOS technology, is sensitive to magnetic fields perpendicular to the chip surface. The output of the MCO is a square wave whose frequency varies linearly with, and is modulated by, the magnetic input signal.