buck boost converter

[mamadiuze]

l used shotki diode but i have same problem
diode work correctly but i have 3volt at output

 

[tpetar]

l used shotki diode but i have same problem
diode work correctly but i have 3volt at output

I'm afraid that you need to supply additional informations about this, such as circuit diagram, power voltage source and expecting destination voltage and current.



Best regards,
Peter

 

[mamadiuze]

Hi
I want to build a buck boost converter with 5 to 12 input voltage. I want to fix output voltage at 12 volt.
I used this components :
f :20khz( use pwm pulse from avr microcontroller)
GH20N50 IGBT
120micro farad 400 v capacitor
Inductor 4.7 mh
6A10 diode
12 volt 20 watt halogen lamp as load
I drived IGBT with two BD139 transistor and it work properly.so I think driving circuit is true and igbt have no problem. but when I add diode ,inductor ,capacitor and load I don’t have any voltage at output.
I don’t know what is problem. Please help me. Thank you very much.