GMRの原理を利用したのがあるな
　Magnetoresistive insulators for contactless signal transmission between two electrically
isolated parts of electrical circuits were first demonstrated in 1997 as an alternative to opto-isolators.
A Wheatstone bridge of four identical GMR devices is insensitive to a uniform magnetic field and
reacts only when the field directions are antiparallel in the neighboring arms of the bridge.
Such devices were reported in 2003 and may be used as rectifiers with a linear frequency response.[30]

IL260　１１０Mbps　絶縁６Kvrms　だな。