How do calculate / determine the reference voltage for the error amplifier of my analog PWM generator for a 0-100% duty cycle
Currently with R3 at 10k you get +/-50% duty cycle changes for +/- 0.5 volts centred on 2.5 volts. You want this to be +/- 2.5 volts so, make R3 five times bigger at 50 kohm.