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TPS61087: Constant current with boost converter

Part Number: TPS61087

HI all

I have large ELCO capacitor at output that i have to charge with Constant current ( CC). Can i achieve this with TPS6198 or is there a better solution?

1) I want to limit current with SS pin, can i connect a DAC voltage to SS pin do this?

2) Also i van to change the output voltage, also can i connect the DAC voltage to feedback pin?

3) How is the SS voltage relation to output current and voltage?

Here is a block diagram

Thank you,

BR.

  • Dear Sir,

    The boost converter can't support such design And the SS pin has nothing to do with the charge current.

    You can refer to the SLVA912 to check whether it is helpful.

  • Dear Helen,

    please can you tell me where is the problem with the configuration?

    1) I can add current to feedback pin to have adjustable output voltage ? is this right?

    2) Is the Cout of 400uF to large?

    3) Can this or some other boost converter have a controlled current CC?

    4) What will happen if i put a constant voltage on SS pin?

    Br.
  • Dear Sir,

    Yes, you can add current to the FB pin to adjust the output voltage. It is OK!

    400uF is not a big cap. Actually, for the TPS61087, it could startup normally with this 400uF cap. No extra CC circuit needed.

    We have a boost with CC function, but this part only support 6V output.

    If there's a constant voltage on the SS pin, it will effect the softstart, or even the normal operation because the SS pin voltage is related to the COMP voltage level. So this is not suggested.