PWM+RC Circuit Analysis

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PWM+RC Circuit Analysis [Copy link]

When designing a PWM wave RC filter circuit, the time constant should be determined based on the response time requirements, and the RC time constant should be much larger than the PWM cycle. The RC charge and discharge time constants should be as equal as possible. In addition, the RC parameters should be determined based on the voltage accuracy requirements.

Output voltage = PWM voltage * duty cycle

As shown in the figure above, 1.49v = 5v * 30%

When analyzing the amplitude-frequency response, an AC signal source should be included in the circuit.