bq76920EVM Problems

Osman Cakmak

Other Parts Discussed in Thread: BQ76920, BQ78350, BQ76920EVM

hi, I am using bq76920 EVM and my battery back is 4 series and ~300 Ah. The bq78350 up to 320 Ah but design capacity is maximum 32767 mAh. Design cWh is maximum 32767. How can I resolve the problem?

second question;
When the battery is connected for a long time, the battery is running low when not in use. Where is that much power being spent.

over 8 years ago

0 ThomasCosby over 8 years ago

TI__Guru 73830 points

Osman,

You will need to use current and capacity scaling to support pack capacities greater than 29Ahr. The attached applications report discusses this process. On the second question, are you asking why the pack discharges when it sets idle for a long time? The IC's do draw some current, but it is not significant. Could there be another load present as well? How much capacity is being discharged from the cells?

Tom

3482.High cell count app note.pdf

0 Osman Cakmak over 8 years ago in reply to ThomasCosby

Prodigy 80 points

when I measure the current drawn by bq76920evm with any load, current is 30mA. Is not that a little too much? My 5s test battery is 2000 mAh and 30mAx24H=720mA. what is the wrong?

For 4 series battery; Is this the connection for this battery as I understand it? I think it's wrong because it's not working

0 Osman Cakmak over 8 years ago in reply to Osman Cakmak

Prodigy 80 points

revise: 30 mA without load

0 ThomasCosby over 8 years ago in reply to Osman Cakmak

TI__Guru 73830 points

Are you using the resistor cell simulator that is on the EVM? This places a set fo 200 ohm resistors across the cells and draws current in the 20 to 30mA range.

Power management

Power management forum

bq76920EVM Problems