BQ40Z80: Could BQ40Z80 support the topology with separated charging and discharging terminals?

Andrew Su

Part Number: BQ40Z80

as the typical application schematics in BQ40Z80, there is only topology showed which has only 1 terminal, the discharging current will have to go through the charging MOS. the customers are wondering if BQ40Z80 can support to separate charging and discharging terminals? so the discharging current may not necessary to go through the charging MOS.

thanks!

over 5 years ago

0 Kang Kang over 5 years ago

TI__Mastermind 24870 points

Hello Andrew,

Can you clarify your question? I believe it can support multiple charging/discharging terminals, but you will need to provide a schematic if we need to review it.

0 Andrew Su over 5 years ago in reply to Kang Kang

TI__Intellectual 1645 points

Dear Kang,

please refer to the below topologies. could BQ40Z80 support them?

thanks!

0 Andy Liu (BMS) over 5 years ago in reply to Andrew Su

TI__Guru 52115 points

Hello Andrew,

The pictures did not come through, can you repost in different format?

0 Andrew Su over 5 years ago in reply to Andy Liu (BMS)

TI__Intellectual 1645 points

the first is half-separated topology and the second is the fully-separated topology, the charging and discharging ports are separated.

please help to have a look.

thanks!

0 Kang Kang over 5 years ago in reply to Andrew Su

TI__Mastermind 24870 points

Hello Andrew,

I'm not sure if this will necessarily work. What happens when there is a CUV event?

I still think the best way is to follow the EVM guidelines.

0 Andrew Su over 5 years ago in reply to Kang Kang

TI__Intellectual 1645 points

Dear Kang,

the customers may need to separate charge/discharge ports, it is very common. Our EVM just support charge/discharge MOS in series.

BQ40Z80 has VCC (connected to the conjunction of discharge and charge MOS) and PACK pins, so it might have chance to be able to support separated discharge/charge ports, so the customers want us to confirm.

thanks!

0 Kang Kang over 5 years ago in reply to Andrew Su

TI__Mastermind 24870 points

Hello Andrew,

The datasheet says VCC pin provides power to the bq40z80. It cannot drive a separate discharge or charge port. It is not a charge pump output.

Thanks

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BQ40Z80: Could BQ40Z80 support the topology with separated charging and discharging terminals?