Mehmet,

I don't know about the availability but GEC Plessey Semiconductors had some nice chips as required by you.

MA818 Three-Phase PWM Generator
MA828 Same as above

I remember, once i tried to find these chips on internet but could not get any useful info. Try your luck

I am refering to Sep. 1991 data book "Consumer IC handbook" from GEC Plessey.

IA