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TPS7B82-Q1: Transient responce (Band width for control, cross over freqency)

Yusuke Mukuno
Expert 7395 points
Part Number: TPS7B82-Q1
Other Parts Discussed in Thread: TPS7B83-Q1, TPS7B84-Q1, TPS7B85-Q1, TPS7B86-Q1, TPS7B87-Q1, TPS7B88-Q1

Hi Expert,

Do you have any data for Transient responce performance for the folliowing LDOs.

Band width for control, cross over freqency someting like that.

-TPS7B82-Q1

-TPS7B83/4/5/6/7/8-Q1

Also, do you have any recoomended device for first resonce?

Vin = car battery 8V~16V/ 36Vmax

Vout = 5V

Iout= 200mA

Thanks

Mukuno

  • 0
    TI__Genius 12511 points

    Hi Mukuno-san,

    We do not provide specific bandwidth ranges for our devices/cross over frequencies. Generally speaking the bandwidth cuts off in the MHz range. We show transient behavior in the graphs on the datasheet with line/load transients. Additionally the control loop contains the output capacitor which changes the crossover frequency for the loop so it is dependent upon the application specifically, as for the part recommendation, I am going to loop in a product marketing engineer to help so you get the best selection for your application.

    Regards,

    John

  • 0 in reply to John Schneider
    TI__Expert 7395 points

    John-san

    TPS7B82-Q1 don't have any data(waveform) for showing load transient in the datasheet. (there is the load regulation data, however I would like to know transient responce)

    Do you have any waveform data to show load transient with TPS7B82? it is ok with typical TI usecase capatiror.

    I would like to conpare it with another devices.

    Thanks

    Muk

  • 0 in reply to Yusuke Mukuno
    TI__Expert 4381 points

    Hello Mukuno-san, 

    Here is a comparison between the parts you mentioned. Let me know if you have any questions or want to look at other parts. These are the parts that I would recommend using as well. I would also recommend using a thermally efficient package as these are large power conversions. I would also take a look at An empirical analysis of the impact of board layout on LDO thermal performance (ti.com) to be sure to make a thermally efficient board as well. Let me know if you have any questions. 

      TPS7B82-Q1 TPS7B83-Q1 TPS7B84-Q1 TPS7B85-Q1 TPS7B86-Q1 TPS7B87-Q1 TPS7B88-Q1
    AEC Q100 YES YES YES YES YES YES YES
    Output Options Fixed Output Fixed Output Adjustable Output, Fixed Output Fixed Output Fixed Output, Adjustable Output Fixed Output Fixed Output
    Iout (Max) (A) 0.3 0.15 0.15 0.15 0.5 0.5 0.5
    Vin (Max) (V) 40 40 40 40 40 40 40
    Vin (Min) (V) 3 3 3 3 3 3 3
    Vout (Max) (V) 5 5 18 5 18 5 5
    Vout (Min) (V) 3.3 3.3 1.2 3.3 1.2 3.3 3.3
    Fixed Output Options (V) 3.3, 5 3.3, 5 3.3, 5 3.3, 5 3.3, 5 3.3, 5 3.3, 5
    Enable YES NO YES YES YES NO NO
    Power Good NO NO NO YES NO YES NO
    Output Capacitor Type Ceramic - - - Ceramic Ceramic Ceramic
    PSRR @ 100KHz (dB) 25 70 65 70 65 70 65
    Noise (uVrms) 450 280 280 280 280 252 280
    Accuracy (%) 2 1 0.75 1.5 1 0.85 1.15
    Vdo (Typ) (mV) 400 160 155 100 370 360 390
    Iq (Typ) (mA) 0.003 0.02 0.018 0.02 0.02 0.017 0.017
    Thermal Resistance θJA (°C/W) 59 77.1 50.8 47 29.7 29.7 30
    Min Package Area (mm2) 4 45.5 9 9 19.071 19.071 66.726
    Package Type HTSSOP, HVSSOP, TO-252, WSON SOT-223 SON, SOT-223 VSON SO PowerPAD, TO-252 SO PowerPAD, TO-252 TO-252
  • 0 in reply to McKyla Beuttler
    TI__Expert 7395 points

    Is it meaning, we don't have any data for load transent for TPS7B82-Q1?

    Do you have the wavefrom for load transient for TPS7B82-Q1? (like figure6-15 to figure6-20 of TPS7B85-Q1 datasheet case)

  • 0 in reply to Yusuke Mukuno
    TI__Genius 12511 points

    Hi Mukuno-san,

    Sorry for the confusion, I didn't see that the TPS7B82-Q1 specifically did not include these plots on our datasheet as these are standard to include. I will speak with the team and get back to you if we have the data. 

    Regards,

    John

  • 0 in reply to John Schneider
    TI__Genius 12511 points

    Hi Mukuno-san,

    To see general behavior, I've captured the following:

    Here is a 3.3VOUT 1A/us Load transient from 0-100mA zoom on Rise:

    Here is it zoomed out:

    Is there specific conditions that you'd like to test?

    Regards,

    John