BQ25790: VSYS regulation

Hideki Hayashi1

Part Number: BQ25790

Hi team,

Can you please teach me how the VSYS voltage regulated when the battery exists? Just same as battery voltage? OR VSYSMAX_REG_ACC?

And if the battery voltage falls below VBATMIN, SYS output voltage becomes VSYSMIN_REG_ACC?

Regards,

Hayashi

over 2 years ago

0 Tommy Lin over 2 years ago

TI__Mastermind 32960 points

Hi Hayashi-san,

I will get back to you by end of tomorrow as TI US is on holiday today.

Regards.

+1 Tommy Lin over 2 years ago

TI__Mastermind 32960 points

Hi Hiyashi-san,

When the battery exists, the system voltage will be regulated to battery voltage + 200mV, which is shown in the EC table (VSYSMAX_REG_ACC).

When the battery voltage < VSYSMIN or falls below VBATMIN (depleted battery), the system voltage will be regulated to VSYSMIN + 200mV (also shown in the EC table). The VSYSMIN is determined by the battery cell setting, For example, for a 2S battery, the VSYSMIN will be 7V and if the battery voltage is below VSYSMIN or VBATMIN, the system voltage will be regulated to 7.2V.

Regards

0 Hideki Hayashi1 over 2 years ago in reply to Tommy Lin

TI__Expert 8560 points

Hi Tommy,

Thanks! Very cleared.

I would like to confirm a thing, that is VSYSMIN just depends on the number of cells? Doesn't it depend on battery charging profile?

Regards

0 Tommy Lin over 2 years ago in reply to Hideki Hayashi1

TI__Mastermind 32960 points

Hi Hayashi-san,

Yes, that is correct.

Regards.

Power management

Power management forum

BQ25790: VSYS regulation