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Rtt vs Co values for PTH08T210W, PTH08T240W and PTH08T230W design

Other Parts Discussed in Thread: PTH08T240W, PTH08T210W, PTH08T230W

Hi, 

We would like to find the correct Rtt for C0 values in our PTH08T210W, PTH08T240W and PTH08T230W design.

In the datasheet, the Co is the total output capacitance. Is that means, Co include all the capacitance on the same

power rail ("Right" at the TI power module and close to the IC chip) ? 

1) PTH08T210W design.

    Co = 7100 uF([close to PTH08T210W]: 660 uf POSTCAP + 94 uF ceramic

                           [close to IC]:  6120 uF Tantalum + 226 uF ceramic)

    Rtt = ?

    Question: Will total capacitance(7100 uF) too much ?

2) PTH08T240W design.

   Co = 3533 uF([close to PTH08T240W]: 330 uF POSTCAP + 94uF ceramic

                          [close to IC]:  3109 uF ceramic)

    Rtt = ?

        Question: Will total capacitance(3533 uF) too much ?

3) PTH08T230W design

  a. Co = 1458 uF([close to PTH08T230W]: 330 uF POSTCAP + 94 uF

                             [close to IC]:  680 uF Tantalum + 354 uF ceramic)

    Rtt = ?

    Question: Will total capacitance(1458 uF) too much ?

  b. Co = 1832 uF([close to PTH08T230W]: 330 uF POSTCAP + 94 uF

                             [close to IC]:  1496 uF ceramic)

    Rtt = ?

    Question: Will total capacitance(1832 uF) too much ?

Thanks!!