Well, not Mickey Mouse precisely... but Wayne Allwine, who voiced Mickey beginning in 1983, inheriting the Mickey Mantle (as it were) from Jimmy MacDonald, who had himself inherited it from Walt Disney.
Allwine passed away May 18 from complications of diabetes - and from repeatedly having his nutsack squeezed in a vise in order to propel his voice into those upper octaves.
Requiescat in pace, good Mr. Allwine. You leave an enviable legacy: Your squeaky voice will live on for centuries after you, embedded in late 20th-century American culture like unto a fly in amber. It is no small honor.
[Tip o’ th’ Elisson fedora to Cartoon Brew for the background.]