Bad behavior of VSYS using BQ24161

Noam Weidenfeld1

Intellectual 780 points

Other Parts Discussed in Thread: BQ24161

Hi,

When I am using the BQ24161 with an AC adapter I get a fault condition over the VSYS (See attached)

Every time a battery detection cycle starts the VSYS falls and the VBAT looks corrupted.

It doesn't happen when I use the USB as the power source or when I use a power supply from a different vendor.

There is no battery connected when I am doing these measurements

What can be the reason for this behavior?

Regards

Noam.

over 12 years ago

0 Jeff F over 12 years ago

TI__Guru**** 167096 points

If you include VIN on your plot, I think you see that it is drooping at the same time VSYS is drooping for the same ~ 32ms. If so, then the adapater is falling the bad source detection circuit.

0 Noam Weidenfeld1 over 12 years ago in reply to Jeff F

Intellectual 780 points

Jeff Thanks,

Attached is a picture showing VIN and VBAT

Do you think that the AC adapter can't handle the current change? It is a 5V/3A power supply and the load during the test is minimal.

0 Jeff F over 12 years ago in reply to Noam Weidenfeld1

TI__Guru**** 167096 points

There is very little load during battery detection. Is SYS loaded? There does appear to be a spike falling on VIN. Can you zoom in? What do the USB and other power supply show?

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Bad behavior of VSYS using BQ24161