• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 63 subscribers
  • Views 335 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.

TPS3851-Q1: TPS3851-Q1 maximum time from VPOR to RESET(Low)

Akihisa Tamazaki
Genius 10805 points
Part Number: TPS3851-Q1
Other Parts Discussed in Thread: TPS3851

Hello team,

I received the question from the customer  about TPS3851-Q1 RESET.

In the datasheet, ". During startup, the state of RESET is undefined below the specified power-on-reset (POR) voltage (VPOR). Above POR, RESET goes low and remains low,"  The  question is that the maximum time from the undefined status to RESET LOW status as below.
Would you please advise? 

Your advice would be so appreciated.

Best Regards,
Akihisa Tamazaki

  • 0
    TI__Genius 9375 points
    Tamazaki-San,

    This time depends on the slew rate of your Vdd. Since RESET is undefined below VPOR, the time that it takes for your Vdd to reach VPOR will be the time that the RESET stays undefined.

    Thanks,
    Abhinav.
  • 0 in reply to Abhinav.Sharma
    TI__Genius 10805 points

    Abhinav-san,

    Thank you for your reply.

    The customer did not ask us the time from start-up to RESET Low controlled by TPS3851. The customer has a question about the time from beyond the VPOR until RESET out controled by TPS3851 become low. Is this also undefined?

    Best Regards,
    Akihisa Tamazaki

  • 0 in reply to Akihisa Tamazaki
    TI__Mastermind 28980 points
    Hi Tamazaki-San,

    1. VPOR is as a technical specification we define to describe at what VDD voltage (often in the hundred of millivolts)the output, which is currently undefined, will reach a maximum "low" voltage. This technical specification defines the input voltage for this transient condition, though often specified is the maximum "low" output voltage with it.

    2. Once, VPOR is exceeded (and below the device threshold), the output power stage is defined (and low), but the internal logic is not turned on/working. Once the device's Vdd,min specification is reached all of the datasheet specifications can be guaranteed.
  • 0 in reply to Marshall_Beck
    TI__Genius 10805 points
    Marshall-san, Abhinav-san,

    Thank you so much for your comment.
    If the customer has additional question, may I ask you again?

    Best Regards,
    Akihisa Tamazaki