Hi Ricardo

I have re-read your post a few times..
And I still think your approach is wrong.

The original circuit may be at TTL level - but I expect that the output is still PWM by sine table to control the voltage and frequency.

Is the drive you are modifying one of the older (circa 1980's ) drives that used a rotating field created by a sine wave stored in an eprom , and comparators for the outputs?.


I have recently re-manufactured 39 10kw 3ph inverters that used that approach and can assure you that the quickest and best way is to use the Infineon chips and their examples as a base to start with.

Will you be required to comply with EMC regulation for this?. .