PI Controller DC-DC Buck Converter with PIC16F877A

[Eshnur]

Hi. How can i add PI Controller on this circuit? btw this circuit works on ISIS but its doesn't work in real life could you help me?
https://imgur.com/n1MAmAf this is circuit
and codes

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Code C - [expand]
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void main()
{
   set_tris_a(0xFF);     
   set_tris_c(0x01);    
  
   setup_timer_2(T2_DIV_BY_1,255,1);
   setup_CCP1(CCP_PWM);
   
   int buton_1,buton_2,buton_3,buton_4;  
   int16 Duty=0;
   float YuzdeDuty;
   set_pwm1_duty(Duty);
   
   while(TRUE)
   {  
   
     buton_1=input(pin_A0);
     buton_2=input(pin_A1);
     buton_3=input(pin_A2); 
     buton_4=input(pin_A3); 
     
     if(buton_1 == 1 && buton_2 == 0 && buton_3 == 0 && buton_4 == 0) 
     { 
     delay_ms(20);
     Duty=250;
  //   YuzdeDuty=25;
     set_pwm1_duty(Duty);
    // output_d(YuzdeDuty);
     } 
     
     else if(buton_2 == 1 && buton_1 == 0 && buton_3 == 0 && buton_4 == 0)
     { 
     delay_ms(20);
     Duty=400;
    // YuzdeDuty=50;
     set_pwm1_duty(Duty);
     //output_d(YuzdeDuty);
     } 
     
     else if(buton_3 == 1 && buton_1 == 0 && buton_2 == 0 && buton_4 == 0)
     { 
     delay_ms(20);
     Duty=600;
     //YuzdeDuty=75;
     set_pwm1_duty(Duty);
     //output_d(YuzdeDuty);
     }
     
     else if(buton_4 == 1 && buton_1 == 0 && buton_2 == 0 && buton_3 == 0)
     { 
     delay_ms(20);
     Duty=850;
     //YuzdeDuty=100;
     set_pwm1_duty(Duty);
     //output_d(YuzdeDuty);
     } 
   }
 
}

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[Akanimo]

Hi,

Should you not be using a MOSFET driver where you are using the 3904 transistor?

 

[KlausST]

Hi,

C1, C2 value is not useful.

Please check not to overdrive V_gs of the Mosfet.

Why don't you use low side switching? (More simple)

"Doesn't work" is no useful error description. Please tell us what not is like expected.

Klaus

 

[Eshnur]

"C1, C2 value is not useful." is 22pF suitable?
"Please check not to overdrive V_gs of the Mosfet." should i add 12v battery between G and S
Why don't you use low side switching? (More simple)" because i have to use high side as i know, can i make low side driver buck converter?
""Doesn't work" is no useful error description. Please tell us what not is like expected." i will give more knowledge after i test with osilascope

 

[Eshnur]

i don't understand could you explain please?

 

[BradtheRad]

can i make low side driver buck converter?

Rearrange the usual schematic, so that the converter is referenced to the positive supply rail:

 

[Akanimo]

Without adequate inductance in the power stage the converter will not work. In your schematic there is no inductance at all.