Help in BUCK converter Please!

[biomeeg]

Hi all bro!
I'm a beginer and I have a project which need a power supply with input voltage about 110VDC and variable output from 5V to 80-90VDC,I out<=500mA. Output voltage controled by microcontroller via IR2110 to driver MOSFET. But I don't know how to calculate value of components on BUCK circuit(boot capacitor,Inductor and output filter capacitor).
Please tell me that can make that power supply and how? Thanks so much.

 

[masa_2010]

Hi

I think that you will find what you need at the attached paper.

In this paper you will find how to calculate the minimum inductor and capacitor values. The inductor value is determined based on your switching frequency. The minimum value of inductor is the value that make buck converter operates at CCM (i.e inductor current never go to zero). The capacitor value will be determined based on the maximum output ripple that you design allow.

 

[Tahmid]

Hi,

Have you drawn a schematic? If so, please upload it so we can see it and help in choosing the component values.

Are you familiar with microcontroller programming?

Tahmid.