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TLV61290: Boost with lowest ripple

d_zero
Genius 4775 points
Part Number: TLV61290
Other Parts Discussed in Thread: TPSM83100, , TPSM81033, TPSM83102, TPS61299, TPS62913, TPSM81299

Tool/software:

Dear All,

we are looking for a boost DC/DC converter or module that can boost from 3.3V to 3.75V at max current consumption below 100mA ( ~ 90mA)

The power supply will be used for an analog rail so we would like to have smallest noise.

Noise density (V/Hz0.5)  line

from 1.E+00 (Hz) to 1.E+04 (Hz) -> falling from 3.E-05 (V/Hz0.5)  to 3.E-07 (V/Hz0.5)  [ -10 dB/decade]

from 1.E+04 (Hz) to 1.E+06 (Hz) -> 3.E-07 (V/Hz0.5)  

from 1.E+06 (Hz) to 1.E+08 (Hz) -> falling from 3.E-07 (V/Hz0.5)  to 3.E-09 (V/Hz0.5)  [ -20 dB/decade]

Please can you propose your best converter ( eg TLV61290 or any other) or module ( eg. TPSM83100 , TPSM81033, TPSM83102 or any other) that can meet the criteria?

Please note that the main factor is ripple/noise -> small form factor -> efficiency.

Also would you for this application consider a charge pump?

Best Regards,

d.

  • 0
    TI__Genius 13305 points

    Hi d,

    TPS61299 uner 100mA load is about 10mV, could the customer accept that?

    Otherwise what is the expected efficiency？

  • 0 in reply to Nini Zhong
    Genius 4775 points

    Dear Nini,

    we are the customer, we will look into it.

    Questions:

    a) how can we compare 10mV ripple to the Noise density (V/Hz0.5)

    b) Do you have some app not on how with additional Vout filter we can achieve even better noise performance regarding to boost converter stability?

    c) This device needs external inductor, does any device with integrated inductor from TI portfolio come close to the noise performance of TPS61299 ?

    Best Regards,

    d.

  • 0 in reply to d_zero
    TI__Genius 13305 points

    Hi d,

    I have to say I have no idea how to compare the 10mV to V/Hz^0.5.

    You could refer to the TPS62913 to add LC filter to mitigate the noise.

    Module TPSM81299 is recommended, which performance is similar with TPS61299.

  • 0 in reply to Nini Zhong
    Genius 4775 points

    Dear Nini,

    i think that 10mV is probably to much, we need to filter it with passive filter or second stage LDO.

    the system integrator must ensure that the noise density on AVDD is below the limits defined in the figure below


    We have noise density vs. frequency profile and want to relate it to a ripple (10 mV). is the 10mV RMS or Vpp?

    I think we need to do is integrate the noise density over the frequency range to get an RMS voltage, then compare that RMS to your ripple.

    Do you think is that the correct way?

    Best Regards,

    d.

  • 0 in reply to d_zero
    TI__Genius 13305 points

    Hi d,

    the 10mV is Vpp, at about 3MHz.

    Your way makes sense. An LDO is better included in your design to minimize the PSRR.