• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 63 subscribers
  • Views 245 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.

BQ24072T EMC issue when charging

oystein.kristiansen
Prodigy 40 points
Other Parts Discussed in Thread: BQ24072T

Hi


We have developed a product with BQ24072T onboard. We are now in the phase for CE certification and without battery everything is OK. But when we insert a lithium polymer battery the noise floor and noise peaks rises in the sub giga hertz range. The base frequency seems to be 34.451 MHz and it rises about 10dBuV/m measuered 10 meters away. The limit is 30 dBuV/m. Without battery it goes down to 22dBuV/m.

I tried to read the documentation for this IC, but I could not find anything about internal clock inside it or how to solve it.

Any ideas why this happens and how to solve it?


BR

Øystein Kristiansen

  • 0
    TI__Genius 13700 points

    Hello,

    Could you provide a schematic of the system to understand what the surrounding factors might be?

    The fact that this a linear charger with a feedback loop that operates substantially below the frequency you are observing has me wondering if the addition of the battery is simply increasing the load upstream causing the increased noise.