Nyob rau hauv xyoo tsis ntev los no, tiam sis nyob rau hauv tsheb thiab lwm yam kev lag luam tau spiked thov rau tshiab magnetic ntaub ntawv.Raws li qhov tshwm sim, nyob rau hauv nruab nrab-1990s thawj cov khoom tsim los ntawmsoft magnetic compositeyug.Thiab cov qauv ntawm kev siv cov mos sib nqus sib nqus (SMCs) tsuas yog txuas ntxiv mus.

Cov thawj SMC qhov chaw yog ignition cores, siv ntau nyob rau hauv feem ntau GM tsheb.Lawv tau compacted puag ncig, thiab tsis muaj daim kab xev insulating siv los tiv thaiv thawj winding los ntawm kauj.Ceev nrooj rau hnub no, thiab hmoov hlau - thiab SMC - tshuab tau los ntev.Nyeem ntawv kom kawm paub cov hauv paus ntawm cov khoom sib nqus sib nqus thiab qhov ua rau lawv tseem ceeb heev rau cov khoom siv hluav taws xob hauv ntau qhov kev lag luam.