BQ25713: Charge status thresholds

Charles Jenkins59

Part Number: BQ25713
Other Parts Discussed in Thread: BQ25792,

The 25713 is missing the Battery Charging Profile as in figure 8-9 of the BQ25792 data sheet. Instead charger status transitions are a function of the minimum system voltage setting? Is this correct?

On the 25713 EVM and our system using that part the charger status goes from precharge to fast charge status when the charger is putting out high current. But when the current tapers off to single mA charge currents the charger status still indicates Fast Charge. When does the status reset itself to not charging? Do we have to do something to reset the status?

over 2 years ago

0 Khalid Bairuti over 2 years ago

TI__Expert 4780 points

Hello Charles,

The BQ25713 does not have a charge termination function - the host needs to determine when to terminate charging. BQ25792 on the other hand does have a termination function.

For BQ25713, when battery is full or battery is not in good condition to charge, host terminates charge by setting REG0x00[0] to 1, or setting ChargeCurrent() to zero.

With regards to the IN_PCHRG and IN_FCHRG, these only denote whether the device is in Pre-charging or Fast-Charging mode, where the transition point is the value that VSYS_MIN is programmed to (Register 0x0D/0x0C). Since the device does not have a charge termination function, there is no explicit termination indicator.

Here are a couple similar threads on other Buck-Boost chargers in our family.

https://e2e.ti.com/support/power-management-group/power-management---internal/f/power-management---internal-forum/1115402/bq25730-charge-termination?tisearch=e2e-sitesearch&keymatch=in_fchrg#

https://e2e.ti.com/support/power-management-group/power-management/f/power-management-forum/847819/bq25703a-way-to-detect-when-quick-charge-is-finished/3135187?tisearch=e2e-sitesearch&keymatch=in_fchrg#3135187

Thanks,

Khalid

0 Charles Jenkins59 over 2 years ago

Intellectual 360 points

Thank you Khalid. I will review the links below. We are forced to use the 713 as it was the only charger that was available. Our preferred charger would have been the 25798 as we are attempting to use the 713 with solar.

One item that gets in our way consistently with most of the chargers is the DPM function. When the voltage is first applied to Vbus, DPM sets the input voltage. A few volts less than this voltage and the device shuts down. Can DPM be turned off on the 713?

Yes was can manually set this lower but this will be an issue if every time the solar panel sees flux, we need to set a new input voltage.

0 Khalid Bairuti over 2 years ago in reply to Charles Jenkins59

TI__Expert 4780 points

Hello Charles,

There isn't a setting to outright disable the VINDPM. You can set the InputVoltage() register sufficiently low (or to 0) to get it out of the way. Note that it needs to be done after the Charger automatically sets it on adapter insertion.

Thanks,

Khalid

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BQ25713: Charge status thresholds