BQ21040: Is it possible to use this part to charge individual cells?

Justin Barker

Part Number: BQ21040
Other Parts Discussed in Thread: BQ2057,

I'm planning to use 2 Li-ion cells in series to power a portable headphone amplifier.

Is it possible to use this chip to charge each cell individually and still have a system load of 7.4V or am I missing something?

over 8 years ago

0 Diana Bodenmiller over 8 years ago

TI__Prodigy 640 points

Hello Justin,

bq21040 is a single cell charger. If you mean to charge two cells in series you need a charger that can charge dual-cell such as bq2057

0 Justin Barker over 8 years ago in reply to Diana Bodenmiller

Prodigy 30 points

The cells will be used in series, but charged individually by 2 of these chips. Is there something wrong with that application?

0 Diana Bodenmiller over 8 years ago in reply to Justin Barker

TI__Prodigy 640 points

Hi Justin,

Could you draw this out? I am not seeing how they can be charged separately but remain in series.

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BQ21040: Is it possible to use this part to charge individual cells?