BQ27425-G2_15 Datasheet, PDF (12/39 Pages) Texas Instruments – Fuel Gauge With Integrated Sense Resistor

bq27425-G2
SLUSB23B – OCTOBER 2012 – REVISED JUNE 2015
www.ti.com
Table 2. Battery Detection
Op Config [BIE]
BATTERY INSERTION REQUIREMENT
(1) Host drives BIN pin from logic high to low to signal
battery insertion.
or
1
(2) A weak pullup resistor can be used (between BIN and
V_CC pins). When battery pack with a pulldown resistor is
connected, it can generate a logic low to signal battery
insertion.
0
Host sends BAT_INSERT subcommand to signal battery
insertion.
BATTERY REMOVAL REQUIREMENT
(1) Host drives BIN pin from logic low to high to signal
battery removal.
or
(2) When battery pack with a pulldown resistor is removed,
the weak pullup resistor can generate a logic high to signal
battery removal.
Host sends BAT_REMOVE subcommand to signal battery
removal.
8.4 Device Functional Modes
8.4.1 Operating Modes
The fuel gauge has different operating modes: POR, INITIALIZATION, NORMAL, CONFIG UPDATE, SLEEP,
and HIBERNATE. Upon power up from OFF or SHUTDOWN, a Power On Reset (POR) occurs and the fuel
gauge begins INITIALIZATION. In NORMAL mode, the fuel gauge is fully powered and can execute any
allowable task. Configuration data in RAM and NVM can be updated by the host using the CONFIG UPDATE
mode. In SLEEP mode the fuel gauge turns off the high-frequency oscillator clock to enter a reduced-power
state, periodically taking measurements and performing calculations. In HIBERNATE mode the fuel gauge is in a
very-low-power state, but can be woken up by communication or certain IO activity.
In SHUTDOWN mode, the LDO is disabled so internal power and all volatile data is lost. Because no gauging
occurs in SHUTDOWN mode, additional gauging error can be introduced if the system has significant battery
charge or discharge activity before re-INITIALIZATION.
12
Submit Documentation Feedback
Product Folder Links: bq27425-G2
Copyright © 2012–2015, Texas Instruments Incorporated