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SN6505B: How to know the quiescent current or the efficiency of no load

Part Number: SN6505B

Hi,

   We using SN6505 to implement 3.3V input and isolated 5V output.  It's important the efficiency  for our system. So we want to know the quiescent current or the efficiency  of no load for SN6505.  How to calculate or where we can find it? thanks very much.

  • Hi Leo,

    Since SN6505 is an open-loop (no feedback) push-pull transformer driver, it doesn't employ any lower power mode operations for lower output current loads. For this reason when the load current is zero, the input current for SN6505 is going to be somewhere between 20mA to 30mA.

    Please note that when there is no load connected at the output, the efficiency is always going to be 0% irrespective of what the input current is. Hence, if you could let us know is there any particular efficiency requirement that you need to meet for a particular load current we would be able to let you know if SN6505 meets the requirement. For example, requirement like min 50% efficient for 10% 10mA load.

    SN6505 also comes with Enable pin, if possible you can make an MCU or an analog circuit control SN6505 Enable pin to turn it OFF under no load currents. Thanks.

    Regards,

    Koteshwar Rao

  • Thanks Koteshwar for your quick response. If we have Low no-load power consumption products can be recommended? thanks.

  • Hi Leo,

    It is generally difficult to achieve low power consumption under no load condition. SN6505 is one our best devices for isolated power supply generation. I do not have any other device suggestions that are better than SN6505. Let me know if you have any other questions, thank you.

    Regards,

    Koteshwar Rao