BQ25720: SMBus Autonomous Smart Battery management

Giuliano Talacci

Part Number: BQ25720
Other Parts Discussed in Thread: BQ40Z50,

Tool/software:

Hi,

I am evaluating the battery charger BQ25720 for a new product. This component should communicate via SMBus with a smart battery (3S2P) that integrates the BQ40Z50, in a stand-alone configuration (without a host MCU), as described in application note SLUAAF8.
Unfortunately, I have not yet been able to get the BQ40Z50 to communicate with the BQ25720.

Any suggestion? Is it possible to get some application example of this configuration?

Thanks

2 months ago

0 Tiger Zhou 2 months ago

TI__Mastermind 32845 points

Hi, Giuliano,

The BQ25720 is a secondary device. It waits for command from the gauge device. BQ25720 stores the default settings inside the chip, every time during power up, it loads the default values.

I think you may need to work on the BQ40Z50 device and set it properly to communicate with the charger. BQ40Z50 can then broadcast the charger voltage and charge current values to the BQ25720.

More details, please refer to the application note.

Regards,

Tiger

0 Giuliano Talacci 2 months ago in reply to Tiger Zhou

Prodigy 10 points

Hi Tiger,

Thanks for the quick reply.
I tried to work on the BQ40Z50, but it is not clear to me which registers are involved in programming the device in Broadcast mode.
Is there any reference to the programming code?

Thanks

Giuliano

0 Tiger Zhou 2 months ago in reply to Giuliano Talacci

TI__Mastermind 32845 points

BQ40Z50-R5 Technical Reference Manual (Rev. B)

https://www.ti.com/lit/pdf/sluucn4

Power management

Power management forum

BQ25720: SMBus Autonomous Smart Battery management