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LT8210 Power Supply Design

Category: Hardware
Product Number: LT8210

Hi. I have a question about LT8210. I want to design a power supply which should have an input of 9V to 70V and an output of 36V-10A approximately. But when I  try to simulate the circuit I see that with 9V input I cannot get the desired output and with 70V input the circuit behaves really unstable. In the datasheet, I could not find any clue how to calculate compensation components. Could you please help to select required compensation components?

Parents
  • Hi,

    in the data sheet starting at page 33 "Loop Compensation" you find guide lines for the compensation values.
    Unfortunately this matter seems to be too complex for a formula.
    So you have to try different values and see if it gets more stable or less stable.
    Once you got stability, you can optimize regulation for load current jumps.

    Are you aware that at Vin= 9V and Vout= 36V@10A you'll get peak currents (=> MOSFETS and inductor) of  way more than 40A?
    Your inductor must handle that peak currents without saturating.
    Have you made thermal calculations?
    Even if you have a relatively big board, the thermal resistance of your sole board could be about 50K/W or more.

Reply
  • Hi,

    in the data sheet starting at page 33 "Loop Compensation" you find guide lines for the compensation values.
    Unfortunately this matter seems to be too complex for a formula.
    So you have to try different values and see if it gets more stable or less stable.
    Once you got stability, you can optimize regulation for load current jumps.

    Are you aware that at Vin= 9V and Vout= 36V@10A you'll get peak currents (=> MOSFETS and inductor) of  way more than 40A?
    Your inductor must handle that peak currents without saturating.
    Have you made thermal calculations?
    Even if you have a relatively big board, the thermal resistance of your sole board could be about 50K/W or more.

Children
  • Hi,

    Thanks for your quick response. And as you underline I believe that my board will be to carry these peak currents. Also I want ask for your opinion for loop compensation. Is there any starting point for my specifications to try component values? Also, should I select the component values independently for buck region and boost region? If you please share your thoughts I will be grateful.