BQ24032A: Capacitor from ISET1 to BAT

Richard Friederich

Part Number: BQ24032A
Other Parts Discussed in Thread: BQ24074, , BQ24073

11.2.2 of the data sheet says that a 0.22 µF capacitor between BAT and ISET1 will improve operation at low charge currents. However, it is not shown in the typical application schematic, figure 7.

What does "improve operation" mean? Does it damp out potential oscillation? Does it improve accuracy of I=Kset*Vset/Rset? In what way might operation be non-optimal if this capacitor is omitted?

over 6 years ago

0 Raheem over 6 years ago

TI__Mastermind 21590 points

Hello Richard,
It is not included in the typical application schematic because that application was for 1A charging. What charging current are do you require for your application? Please take a look at the BQ24073 or the BQ24074 which are similar to the BQ24032A but have a smaller package.

0 Richard Friederich over 6 years ago in reply to Raheem

Prodigy 240 points

Thank you for the reply, Raheem.
We're using the bq24032A to charge at a nominal 100 mA, at the bottom of its specification. Due to other considerations, we are locked into using this part. Therefore, the questions remain -
What does "improve operation at low charge currents" mean?
In what way might operation be non-optimal if this capacitor is omitted?

0 Raheem over 6 years ago in reply to Richard Friederich

TI__Mastermind 21590 points

Hello Richard,
Please take a look at the link below. This question has been answered there. e2e.ti.com/.../641554

Power management

Power management forum

BQ24032A: Capacitor from ISET1 to BAT