Problem connecting battery BQ24616

Hi,

You are probably experiencing inrush current when connecting the battery, which can cause this problem. You should add inrush control on the battery connection. Can I see a schematic to see if there is any other improvement that can be done?

Regards,
Steven

Hi, 

You could find in attachement  the schema of my circuit.

Thanks 

CAR_061_00_SCH_01.pdf

Hi,

See if you can add RC delay to Q17 and Q20 gates (add C in parallel to R58 and R56, like 0.01uF), which are the two that enable charging for your battery. This will control the turn on time of the FETs and reduce inrush current.

A few things on the schematic for bq24616:
1. No need for R90 and R91
2. By adding R13, you can remove R84 if the switching waveform at PH looks good.

What are the FETs for Q1 and Q2 that are used?

Regards,
Steven

Hi,

Thanks for this informations.

The MOS (Q1 and Q2) used for the charger are IRF6614TRPBF (40V , Direct Fet,).

An other solution that to fixed the problem is to start the charger before to connect the battery, so all the capacitors will be charge and i won't have inrush current!

demarrer

Thanks

Best regards.

Yes that may also be a solution :). Go with what is closer to your application.

Regards,
Steven