BQ25172: Schematic review

Hi Jeff

Double check the connection of Q1 to VSET, should this go to TS?

Other parts of the circuit looks good.

Hi Bill,

Q1 just for control change enable or not, thank you.

Jeff

Hi Jeff

Jeff YANG said:

Q1 just for control change enable or not

Bil J -- If TS is pulled to ground that will work as a charge enable / disable.  But Grounding VSET will not, this pin is only read at power up.

Hi Bill,

The circuit has been corrected as follows. Additionally, there is a question that needs to be confirmed: when the battery is fully charged, and the charging input is removed, then reinserted, will the BQ25172 charge the battery again? How long will the charging take? From the specifications, it seems to be 20% of TMR (according to the circuit in the diagram, will it charge for an additional 2 hours?), or does it depend on the battery voltage, and it will stop once it reaches the predetermined voltage for a 1-cell battery?

Hi Jeff

Jeff YANG said:

The circuit has been corrected as follows.

Bill J - Looks good

Jeff YANG said:

when the battery is fully charged, and the charging input is removed, then reinserted, will the BQ25172 charge the battery again?

Bill J - The charger will check battery voltage, if it is above V-RECHG (1.33V pre cell) the battery is considered full, device does not start charge.

Jeff YANG said:

How long will the charging take?

Bill J - If voltage is below V-RECHG, device will start a full charge cycle, time set by TMR pin.

Jeff YANG said:

From the specifications, it seems to be 20% of TMR (according to the circuit in the diagram, will it charge for an additional 2 hours?),

Bill J - 20% would apply if intermittent charge cycle is set using VSET (47k vs 62k) and this is a recharge after a full charge, voltage drops below recharge level.

Jeff YANG said:

it will stop once it reaches the predetermined voltage for a 1-cell battery?

Bill J - Charge is timer based, will not use cell voltage. Device does have over voltage that will stop charge..

Hi,

Just double check, if using intermittent charge, battery voltage < V-RECHG (1.33).

As charge profile, it will charge 20% x TMR.

If "not" using intermittent charge, battery voltage < V-RECHG (1.33).

As charge profile, it will charge 100% x TMR or until reach OVP, right?

Thanks!

Jeff

Hi Jeff

"Just double check, if using intermittent charge, battery voltage < V-RECHG (1.33). As charge profile, it will charge 20% x TMR." -- Bill J - Yes

"If "not" using intermittent charge, battery voltage < V-RECHG (1.33)." -- Bill J - Yes, no new charge cycle will start.

"As charge profile, it will charge 100% x TMR or until reach OVP, right?"-- Bill J - Yes, new charge cycle (power cycle) will be 100% X TMR.