buck converter design

[venkata harish]

please any one calculate and give the l, c values of buck converter which bucks 17v to 9v. please post the formulas to find l and c values also.i would be very thankful if some one does this for me.

regards
harish

 

[BradtheRad]

Have you tried experimenting (or made simulations) with any values before now?

In general terms, you can switch current on and off through a coil at 55 or 60 percent duty cycle, to do what you are asking.

Typically the operating frequency is chosen to be above the ability of humans to hear.
A coil with a value of 500 uH is okay to start with (as a ballpark figure).
The smoothing capacitor value can start at 10 uF, say. If ripple is too severe then increase it.