• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 344 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.

TPS54302: replace the solution

Denny Huang
Expert 7170 points
Part Number: TPS54302
Other Parts Discussed in Thread: TPS54202

Dear team 

The output current is less than 2A.

The customer would like to use TPS54302 to replace TPS54202. Whether the two device can replace to each other? Which component need to be change?

Because the different switching frequency of two device, the value of inductor is different.

1. For Vo=3.3V, whether customer can use 10uH of inductor on TPS54302?

1. For Vo=5V, whether customer can use 15uH of inductor on TPS54302?

TPS54202

TPS54302

Many thanks

Denny

  • 0
    TI__Mastermind 30551 points

    Hi Denny,

    Yes, they can replace each other. Something to highlight:

    1. Use equation shown below to calculate the minimum value of the output inductor (LMIN):

    KIND is a coefficient that represents the amount of inductor ripple current relative to the maximum output current.

    Switching frequency of TPS54302 is 400kHz while switching frequency of TPS54202 is 500kHz.

    Vin(max), Vout, Iout is the same for TPS54302 and TPS54202, while fsw is different. 

    If you want to follow the same KIND as before, you need to use 12.5uH(Vout=3.3V), 18.75uH(Vout=5V).

    However, the customer can still use 10uH and 15uH for Vout=3.3V and 5V, while it will effect the value of KIND which would be increased.

    2.For designs using low-ESR output capacitors, such as ceramics, a higher KIND can be used. When using higher ESR output capacitors, KIND = 0.2 yields better results. a reasonable value of KIND should be 20% to 60%,

    Let me know if you have more questions.

    BRs

    Lucia