TIPD108: PWM Signal Generator

This circuit utilizes a triangle wave generator and comparator to generate a pulse-width-modulated (PWM) waveform with a duty cycle that is inversely proportional to the input voltage. An op amp and comparator generate a triangular waveform which is passed to the inverting input of a second comparator.

By passing the input voltage to the non-inverting comparator input, a PWM waveform is produced. Negative feedback of the PWM waveform to an error amplifier is utilized to ensure high accuracy and linearity of the output.

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