aggpankaj2
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Hi,
In the attached figure, you can see that a P-FET (Power MOSFET) is to drive a big solenoid which operates at 8A constant current. A current sensing circuit and one or two filters on the line. one MOSFET driver is driving the P-FET (not shown in figure) at certain frequency (assume 10KHz).
Now to calculate the center frequency of PWM, I need to find out the filter values which will help me keeping my output constant (considering with noise my current to Solenoid can vary in between 7.8 to 8.2A) and determining the PWM frequency.
Can somebody make me understand how we calculate those values?
In the attached figure, you can see that a P-FET (Power MOSFET) is to drive a big solenoid which operates at 8A constant current. A current sensing circuit and one or two filters on the line. one MOSFET driver is driving the P-FET (not shown in figure) at certain frequency (assume 10KHz).
Now to calculate the center frequency of PWM, I need to find out the filter values which will help me keeping my output constant (considering with noise my current to Solenoid can vary in between 7.8 to 8.2A) and determining the PWM frequency.
Can somebody make me understand how we calculate those values?