• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 62 subscribers
  • Views 132 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

Original question:

BQ24095: Iset programable

BQ24095: Iset programable

shai oren
Prodigy 20 points
Part Number: BQ24095

I want to design programmable Iout charger with the BQ24095.

I added parallel resistor to the main resistor and put a series FET which his Gate connected to a frequency modulator with variable duty cycle

Does the calculation of the equivalent resistor for Iset is : R1||(R2*D) or R1*(1-D) + R1||(R2*D)

  • 0
    TI__Guru*** 143910 points

    Hi Shai,

    Assuming the frequency is slow enough (<10kHz) to give the charge current loop time settle, the equivalent resistor will be

    R1 when the FET is off and R1||R2 with the FET is on

    R1 is primary resistor

    R2 is secondary resistor in series with NFET connected to GND

    Do you want an equation for the average/mean value of the resistor?  If so then Rmean = { [(R1||R2)*D]^2 + [R1(1-D)]^2}^0.5.

    Regards,

    Jeff