• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 631 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.

LM5069: UVLO Threshold value discrepancy between Design calculator and datasheet

afshin s
Prodigy 10 points

Part Number: LM5069

Hi Team,

I need some help on my circuit design using LM5069.
I am designing a circuit with minimum input voltage 9.3 V. In datasheet it is mentioned that minimum input voltage for this component is 9 V. So it should be OK.But in LM5069 Design Calculator (Rev. C) it does not let me to enter any input voltage less than 10V in "Step5"  in  "Desired Upper UVLO Threshold" cell. comment on that cell says : "This threshold must be between 10V and 80V." and eror pops up when I try to calculate R1,R2 and R3 resistors.
Does it mean that this device is not appropriate for voltages below 10V ( similar to my design)?
Or i should disregard LM5069 Design Calculator (Rev. C) and rely on the numbers in datasheet and calculate my UVLO and OVP resistors manually?

Thanks,

  • 0
    TI__Guru** 107891 points

    Hi Afshin,

    Welcome to E2E!

    The UVLO has tolerance and some hysteresis, so to avoid any overlap of lower UVLO threshold with POREN threshold, the design calculator is restricted with minimum value of 10V.

    To use the device at min Vin voltage, I suggest to connect UVLO/EN pin to Vin through 100k Ohm resistor

    BR, Rakesh