• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 2 answers
  • Subscribers 63 subscribers
  • Views 523 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

Original question:

UCC28C45: COMP Pin Current Limit

UCC28C45: Max COMP Pin Current Limit

Elisha Tarroza71
Expert 3700 points
Part Number: UCC28C45

Hello,

The datasheet specifies the minimum & typical, but not the max source current.
Is there an estimate of the expected maximum source current? Customer is requesting for the value.

Thank you!

  • 0
    TI__Genius 13660 points

    Hi Elisha,

    Did customer get at output driver pin? For output pin, peak output  driver current is ±1A, maximum average output driver current is 200mA.

    Thanks,

    Teng

  • 0 in reply to Teng Feng
    TI__Expert 3700 points

    Hello Teng,

    Thanks for the response, however, the customer is requesting for the max source current of the COMP pin when grounded. The datasheet just mentions the typical and minimum values.

    Thank you!

  • 0 in reply to Elisha Tarroza71
    TI__Genius 13660 points

    Hi Elisha,

    The output stage of the amplifier can source 1 mA typically, Unfortunately, the value information of maximum source current can't be found in the datasheet. 

    We don't recommend customer to source comp pin current larger than 1mA.

    BTW, May I know what's purpose for customer to use comp pin, so that I can give the advice further.

    Regards,

    Teng 

  • 0 in reply to Teng Feng
    TI__Expert 3700 points

    Hello Teng,

    Thank you, the customer will short it COMP pin to GND, as advised in datasheet. Can you please advise the expected maximum current for this?
    The datasheet does mention that it's typically 1mA. Is the maximum just a few uA above this value?

  • 0 in reply to Elisha Tarroza71
    TI__Genius 13660 points

    Hi Elisha,

    In the datasheet in the section 8.3.1.1 is stated: “…… . The error amplifier is internally current-limited, so that one can command zero duty cycle by externally forcing COMP to GND.”. However no value for the current limit is specified at datasheet. And I expect larger current with VCOMP “shorted” to ground.  

    If the customer is worried for excessive power consumption then the datasheet also suggest alternative Enable/Disable methodology in the section 8.3.8. I highlighted one more method in yellow in the snapshot below. I think that pulling the CS pin high could have lower power consumption.

    Regards,

    Teng