BQ25970: one master charger with 2 pcs bq25970 for flash chargers

Zhanpeng Li

Intellectual 2130 points

Part Number: BQ25970

Hi, Teams

We may have some concerns about BQ25970 PCB wiring.

as we can see in BQ25970-EVM, 2pcs of BQ25970 are symmetric in PCB. However, it's difficult to place pcb like this.

Question:

there is no doubt that asymmetrical PCB placement will cause the different resistant in 2 flash chargers. is it tolerant for charging system like this?

over 4 years ago

0 Alen%2520Chen over 4 years ago

TI__Intellectual 2320 points

Hi Zhangpeng,

You are right, that's why it requires a symmetric layout. If it is hart achieve a symmetric layout in real system please make sure they have same impedance at less.

From BQ25970 point of view a little imbalance current won't cause a big problem if the the into each BQ25970 is under it's rating. The main problem would be thermal imbalance, the high current BQ25970 would generate a hotpot.

Alen

Power management

Power management forum

BQ25970: one master charger with 2 pcs bq25970 for flash chargers