• State TI Thinks Resolved
  • Locked Locked
  • Replies 3 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 242 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.

TPS22959: VIN and VBIAS about TPS22959

takahiko yokota
Mastermind 7135 points
Part Number: TPS22959

Hi

Please let me ask you two questions about TPS22959.

・If VBIAS is inputted voltage on VIN=0V, are there any problems?
・I think TPS22959's recommending operation is VIN≦VBIAS.
   Are there the restriction about the start-up  between VIN and VBIAS except  VIN≦VBIAS?

Best regards,
Yokota
  • 0
    TI__Genius 10855 points

    Hi Yokota,

    Thanks for reaching out on E2E!

    Please find the answers to your questions below:

    ・If VBIAS is inputted voltage on VIN=0V, are there any problems?
    [AH]: If EN/ON is high while VBIAS is high and VIN = 0V, then VOUT will follow VIN and output 0V. In this condition, if VIN ramps up to a voltage, then VOUT will follow the voltage on VIN.
    ・I think TPS22959's recommending operation is VIN≦VBIAS.
       Are there the restriction about the start-up  between VIN and VBIAS except  VIN≦VBIAS?
    [AH]: It is generally recommended to have VBIAS and VIN present before EN/ON is enabled. As mentioned above, VIN will follow VOUT if that condition exists. Otherwise, there are no restrictions about the startup in respect to VIN and VBIAS.
    Thanks,
    Arthur Huang
  • 0 in reply to Alpha H
    Mastermind 7135 points
    Hi Huang-san

    Thank you for the reply.
    Please let me confirm you just in case.
    If I change EN/ON from low to high when VBIAS is inputted voltage and VIN=0V,
    there are no restrictions about start-up of VBIAS and VIN.
    Is this understand correct?

    Best regards,
    Yokota
  • 0 in reply to takahiko yokota
    TI__Genius 10855 points

    Hi Yokota, 

    In this scenario, if EN/ON is changed from low to high while VBIAS is high, then VOUT will follow whatever voltage is on VIN. For example, if VIN = 0V, while VBIAS = 3.3V, and EN/ON is changed from low to high, then the voltage on VOUT will be 0V.

    Thanks,

    Arthur Huang