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TPS61041-Q1: Iin AverageI want to know the average current.

Part Number: TPS61041-Q1

Hi all,

Iq is on the data sheet.(P.5)

However, VFB is 1.3 V and it is in no switching operation.

I want to know the average current of current consumption.

When Iout=0mA ,what is the current consumption?


Best Regards
Koji Hayashi

  • What is the input voltage and output voltage in your applicaiton?

    Best Regards,
    Helen

  • In reply to Helen chen:

    Hi Helen,
    Thank you for your quick response.

    My customer specifications are
    Vin:3.06 to 5.33
    Vout:16.6 to 20.0V
    Temp:25C

    Best Regards
    Koji Hayashi
  • In reply to Koji Hayashi:

    The no load current under this input and output voltage range is around 0.6-1mA.

    Best Regards,
    Helen

  • In reply to Helen chen:

    Hi Helen,

    It is high current.
    Is this value from EVM?

    When I checked Iin_Ave by WEBENCH, it was about 150uA.

    Best Regards
    Koji Hayashi
  • In reply to Koji Hayashi:

    Yes.  It is tested from EVM.

    Best Regards,
    Helen

  • In reply to Helen chen:

    Hi Helen,

    Thank you for your quick response.

    When my customer checked following conditions, it was 68uA

    Vin=4.6V,Vout=18,Temp=25C,Iout=0mA

    Is your EVM the same value?

    Best Regards
    Koji Hayashi

  • In reply to Koji Hayashi:

    Hi Koji Hayashi,

    When Vin=4.6V, Vo=18V, Io=0mA, and the VFB not pull high to 1.3V, the no load input current is around 1mA-1.1mA.

    When Vin=4.6V,  Io=0mA, and the VFB is pulled high to 1.3V (no switching), the quiescent current is about 68-70uA.

    Best Regards,
    Helen

  • In reply to Helen chen:

    Hi Helen,

    EVM is 68-70uA.
    However, it is about 28 μA in the Fig.5 of data sheet.

    What is the difference between EVM and data sheet?

    Best Regards
    Koji Hayashi
  • In reply to Koji Hayashi:

    Did they remove the feedback resistor when they test the quicesent current?   The right way to measure this current is remove the upside and low side feedback resistor. add a 1.3V volatge at the FB pin to make the converter no switching. Thus, the tested value is about 25uA in my EVM board.

    My previous testing result 68uA is because I didn't remove the feedback resistor. But quicesent current means the current only consumed by the IC.  so  the feedback resistor must be removed.

    Note: the data in Fig.5 is the typical value. Acturally, there exists lot by lot difference. which is show in the table on page 5. 28-50uA at Vin=2.4V.

    If the customer want to use very low Iq IC, I suggest TPS61093. its maximum Vo can be 17V.

    Best Regards,
    Helen

  • In reply to Helen chen:

    Hi Helen,

    Thank you for four support.

    Customers use for Automobile.
    The TPS61093 is a 1.2-MHz, fixed-frequency.
    Since it is caught in the radio band, TPS61093-Q1 can not be used.

    You wrote like this in the past.
    A:When Vin=3.06 to 5.33V, Vo=16.6 to 20.0V, Io=0mA, and the VFB not pull high to 1.3V, the no load input current is around 0.6mA-1mA.
    B:When Vin=4.6V, Vo=18V, Io=0mA, and the VFB not pull high to 1.3V, the no load input current is around 1mA-1.1mA.

    A is within the condition of B.
    Which one is correct?

    Best Regards
    Koji Hayashi