BQ24090: but its new query

Hello
The diode between BAT pin and Battery may be a problem. During charging the bq24090 will monitor battery voltage at BAT pin. Diode D6 or any other element that changes the voltage can possibly cause charging problems.

Thank you bill for your reply!

The reason we used the mosfet(diode) there is that of when the battery starts of discharge the LED s must not the current from the VBAT output.

as I see the OUT pin is internally connected to mosfet with a diode, is there any chance VBAT current may enter into charging IC?

Is there any resolve this problem?

The /CHG and /PG LED will only be on when the adapter is plugged in and external power is available.
/CHG LED is only on when charging, after charging it will not draw current from the battery. With adapter removed it it off.
/PG is only on when the adapter is present and in charging range. The battery would only discharge to recharge point 4.2V-0.1V, before starting charge.

thanks, bill.

my application involves as follows
as I mentioned in my schematic:
when there is external supply or adapter supply battery should trigger the MOSFETs(controlled by the UC) which are used VIN supply control the charger IC.
At the no supply cycle, charging should stop because we are routing in such way that boost converter supply throughout the PCB ( THIS IS TAKEN CARE BY THE DESIGN).

And the reason I used MOSFET at VOUT is to stop the reverse follow of current( BUT from your input I clarified that reverse flow will affect the charger IC ... is that r8?)

When the power sense the supply the charging has to trigger on, MOSFET at input allows the supply in the charger.

NEED CLARIFICATION

as we realized that external(dg/ups) supply will trigger in 3 mints.
till there, the battery will supply the current to the timer.
I don't think the battery voltage will recharge to 0.1v during this period.

CLARIFICATION, I need is that if the charger will be able to retrieve charging even if the battery voltage is just to 3.6V during discharge?

please help me to solve this issue

Hello
Reverse current protection OUT (battery) to IN (input).
"And the reason I used MOSFET at VOUT is to stop the reverse follow of current( BUT from your input I clarified that reverse flow will affect the charger IC ... is that r8?)"--Bill J -- The bq24090 has built in reverse current protection to prevent current flow from OUT to IN, external protection is not needed. Voltage drop in Diode D5 and mosfet Q3 can cause problems during charging.

Hello

"CLARIFICATION, I need is that if the charger will be able to retrieve charging even if the battery voltage is just to 3.6V during discharge?"---Bill J -- I think retrieve charging is start charging, in this case yes the bq24090 will start charging when battery voltage is less than 4.1V. This is VRCH about 4.2V -0.1V.

Thank bill for all your time!!

thank you for helping me solve issue.