Hi All,
I need help understanding how to analyze this schematic that is attached or at least where to begin. I want to create a voltage controlled PWM circuit. I learned this can be done by inputing a dc voltage and a triangle wave into a comparator. The duty cycle is changed by varying the dc voltage.
I need help understanding the triangle wave generator. I understand how an integrator and a comparator works by themselves. I know integrating a square wave will give a triangle wave.
The feedback and no external input is making this circuit difficult for me to understand. Where and what are the initial conditions? When I look at the circuit on Spice, it looks like having the voltage at vref = 0.5vpp of the triangle wave is critical for the circuit to work. But I don't know how vref becomes 2.5V. I can simulate this on Spice fine and see it working, but I want a deeper understanding of this circuit and learn how to analyze it.
Any help is welcome! Thanks!
I need help understanding how to analyze this schematic that is attached or at least where to begin. I want to create a voltage controlled PWM circuit. I learned this can be done by inputing a dc voltage and a triangle wave into a comparator. The duty cycle is changed by varying the dc voltage.
I need help understanding the triangle wave generator. I understand how an integrator and a comparator works by themselves. I know integrating a square wave will give a triangle wave.
The feedback and no external input is making this circuit difficult for me to understand. Where and what are the initial conditions? When I look at the circuit on Spice, it looks like having the voltage at vref = 0.5vpp of the triangle wave is critical for the circuit to work. But I don't know how vref becomes 2.5V. I can simulate this on Spice fine and see it working, but I want a deeper understanding of this circuit and learn how to analyze it.
Any help is welcome! Thanks!
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