One gate in a 4093 can function as a fixed or variable frequency oscillator, but making it into a PWM driven by an analog voltage is too much for the little critter. Its output is close to 50/50 all the time.

ak

 

If i could use the last part of the CD4093 for the PWM-section or the offset voltage that would be great

Like this:-

 

Like this:-
View attachment 112627

Oh, thats clever. Thanks a lot! Works great in simulation.
Couldnt get it to work with the CD4093, but perhaps thats not needed for this little circuitry.

I have some breadboarding to do now..