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LT3480 low power operation

Category: Hardware
Product Number: LT3480

Hi,

I am designing a power converter with 18-36VIN, 3.3Vout, 0.05A Ioutmax. Due to the shortages of parts, i am looking at using the LT3480 device which is rated for much higher current as it is available for purchase at Digikey. When i perform the design calculations for the inductor at my lower Ioutmax of 0.05A, i get a very high inductor value 207uH compared to the 4.7uH that is on the datasheet's application examples. My question is that if i use the 4.7uH inductor that is on the application examples with my lower Ioutmax will it cause any issues? Is there a minimum output current that must be supplied by the LT3480 in order for it to operate properly?

Thanks

William

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  • FormerMember
    0 FormerMember

Hello William,

The high inductor value is because you have a very low load. By using a lower inductor value, it will have a higher current ripple. It should not cause any problem as long as your converter is stable.

Regards,

Jhun

  • Hi,

    Thank you for the response. If i keep with the 4.7uH inductor that is on the application circuit, the converter stablility at the low operating current is dependent on the RC that is on the Vc pin, is this correct? I can adjust this RC network to ensure stablility, is that correct?

    Thanks

    William

  • Reply
    • Hi,

      Thank you for the response. If i keep with the 4.7uH inductor that is on the application circuit, the converter stablility at the low operating current is dependent on the RC that is on the Vc pin, is this correct? I can adjust this RC network to ensure stablility, is that correct?

      Thanks

      William

    Children
    • FormerMember
      0 FormerMember
    in reply to sungwkn

    Yes That is correct.

    Regards,

    Jhun