• State Resolved
  • Locked Locked
  • Replies 7 replies
  • Subscribers 64 subscribers
  • Views 911 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

TPS62140: TPS62140 - About Simultaneous Power down

Hide
Guru 21045 points
Part Number: TPS62140
Other Parts Discussed in Thread: TPS62135, TINA-TI

Hi Team,

 

I understand that TPS62140 can set the simultaneous start up (VIN1=1.8V and VIN2=1.2V).


 

Can this device set the simultaneous power down?

Could you please let us know if you have any idea?

 

[The sequence that we need]


 

Regards,

Kanemaru

  • 0
    TI__Guru*** 148810 points
    The tracking down behavior should be explained at the top of page 17.

    The TPS62135 in PWM mode supports tracking down.
  • 0 in reply to Chris Glaser
    Guru 21045 points

    Hi Chris-san,

     

    Thank you for your prompt reply.

    I have one more question.

     

    -------

    [Q1]

    May I connect “VOUT1 output” to "SS/TR pin of VOUT2 side" directly without a divided resistor(R1 and R2)?

    And, could you please let us know if you have any concern?


     

    [Background]

    Our customer would like to use VOUT2 = 1.2V when VOUT1 = 1.2V.

    However, according to “Equation 3”, we cannot set “VOUT1=1.2V”(so this equation fails).

     



    -------

     

    Regards,

    Kanemaru

  • 0 in reply to Hide
    TI__Guru*** 148810 points
    If you want to track a 1.2V voltage, please use the TPS62135. There is not enough headroom from 1.2V to the ~1.25V required on SS/TR to get the full 0.8V on the FB pin.
  • 0 in reply to Chris Glaser
    Guru 21045 points

    Hi Chris-san,

    Thank you very much for your help.

    I understand. Thank you very much.

    Regards,

    Kanemaru

  • 0 in reply to Hide
    Guru 21045 points

    Hi Chris-san,

     

    Sorry to ask this of you when you are busy but, I have one more question of TPS62140.

    I understand that after once the SS/TR pin voltage reaches about 1.2V, if SS/TR pin become less than 1.2V, TPS62140 is tracking this voltage (so power down sequence).

    Is my understanding correct?

     

    [Background]

    I simulated this circuit using TINA-TI.

    However, "VOUT2" does not fall the voltage according to "SS/TR voltage".

    (Then, VOUT2 is heavy load)

    Is this the bug of TINA-TI or the correct behavior?

     

    Regards,

    Kanemaru


    TPS62140 VOUT=1.8V and 1.2V.ver2TSC.TSC

     

    Regards,

    Kanemaru

  • 0 in reply to Hide
    TI__Guru*** 148810 points
    After checking with our modeling team, the tracking function was not modeled, so it may not work correctly in the sim.
  • 0 in reply to Chris Glaser
    Guru 21045 points

    Hi Chris-san,

     

    Thank you for the information.

    I greatly appreciate your cooperation.

    I have one more question.

    Is there the plan to improve "TINA-TI model"?

     

    Regards,

    Kanemaru