Voltage Controlled PWM for PAiA FatMan Scott R. Gravenhorst chordman@concentric.net 07-20-96 Add Voltage Controlled Pulse Width Modulation to your PAiA FatMan with one LM324. See drawing PWM.GIF. The summing amp sums the control voltages. This sum is then summed with a bias voltage. This final sum is compared to the inverted FatMan ramp waveform. The output of the comparator is then conditioned for the PAiA FatMan filter input.