• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 1034 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.

TPS763-Q1: Why TPS763-Q1 requires some more ESR compared to other devices?

Ted Zhang
Intellectual 2280 points
Part Number: TPS763-Q1
Other Parts Discussed in Thread: TLV702-Q1

Hi,

Currently I got a question from customer that TPS763-Q1 datasheet mentioned 0.3-10 ESR is needed for a 4.7uF Output capacitor. I checked our part with Rohm's BU33SD2MG(currently on customer's board) and our device need much more ESR than Rohm's. This being said customer should series a resistor at the output(ceramic capacitor's ESR not enough) in order to make sure the stability in all conditions. See below screenshot I take from Rohm's datasheet(First pic) and our datasheet(second pic).

I also checked other LDOs and found that no one specifically pointed out the ESR in application circuit like our TPS763-Q1 did(See below picture). Why TPS763-Q1 requires more ESR compare to others especially Rohm's BU33SD2MG? Can you help this in detail? Thanks

  • 0
    TI__Guru 55940 points
    Hi Ted,

    Please excuse the short delay due to the US Holiday.

    ESR requirements are set in order to help customers compensate the internal circuitry for a stable system. As each LDO part number is a different design, the compensation requirements may not be the same. The following application note goes into a bit more detail on how ESR impacts the stability of an LDO:

    www.ti.com/.../slva115.pdf

    Please consider TLV702-Q1 which is a pin to pin device that is stable with lower ESR.

    Very Respectfully,
    Ryan