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  1. #1
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    Implementing Feedback in Booster Converter Using PIC16F876A

    Hello guys, i work on a boost converter with pic16f876A. anyway the pic works good with duty cycle variable by push butons(manualy). Now the source is without feedback. I read the output voltage in ADC and i want to make some modification:
    -I want to set a output voltage from push butons and the Uc increase the duty cycle auto until the Vout=Vset. If Vout>Vset the uC need to decrease the duty cycle, if the Vset< Vout the uC increase pwm until Vset=Vout. Limits min 12v max 40v (Vout). I want to implementate a feedback. So who can help me?
    I am a bad guy, but I have good intentions!

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  2. #2
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    Re: Implementing Feedback in Booster Converter Using PIC16F876A

    Do you just waht to do these things?

    -I want to set a output voltage from push butons and the Uc increase the duty cycle auto until the Vout=Vset. If Vout>Vset the uC need to decrease the duty cycle, if the Vset< Vout the uC increase pwm until Vset=Vout. Limits min 12v max 40v (Vout).



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  3. #3
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    Re: Implementing Feedback in Booster Converter Using PIC16F876A

    You'll need to make sure the driver operates at or less than 99 percent duty cycle. It must sometimes go to the Off state. It must not go into permanent On-state in an effort to make output rise to your desired level.

    Duty cycle will be different for a given combination of load and desired voltage on it.

    After any change in duty cycle, you'll need to let a few cycles go by, to let output settle to a new value. You'll compare it to your desired level.

    Do you monitor each rise in coil current, and each collapse? This would be done by measuring volt level across a low-ohm resistor inline. This could be a way to verify that current does not rise too high.



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  4. #4
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    Re: Implementing Feedback in Booster Converter Using PIC16F876A

    Hey, in the first post is the source code cound somobody to modify the code? with an output voltaje 24v? And the uc To modify duty cicle for that output?
    I am a bad guy, but I have good intentions!



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