BQ27510-G2 Datasheet, PDF (26/38 Pages) Texas Instruments – System-Side Impedance Track™ Fuel Gauge With Direct Battery Connection

bq27510-G2
SLUS948 – AUGUST 2010
www.ti.com
SLEEP Mode
SLEEP mode is entered automatically if the feature is enabled (Operation Configuration [SLEEP]) = 1) and
AverageCurrent( ) is below the programmable level Sleep Current. Once entry into SLEEP mode has been
qualified, but prior to entering it, the bq27510-G2performs an ADC autocalibration to minimize offset.
During SLEEP mode, the bq27510-G2 periodically takes data measurements and updates its data set. However,
a majority of its time is spent in an idle condition.
The bq27510-G2 exits SLEEP if any entry condition is broken, specifically when:
1. AverageCurrent( ) rises above Sleep Current, or
2. a current in excess of I_WAKE through R_SENSE is detected.
In the event that a battery is removed from the system while a charger is present (and powering the gauge),
Impedance Track™ updates are not necessary. Hence, the fuel gauge enters a state that checks for battery
insertion and does not continue executing the Impedance Track™ algorithm.
SLEEP+ MODE
Compared to the SLEEP mode, SLEEP+ mode has the high frequency oscillator in operation. The
communication delay could be eliminated. The SLEEP+ is entered automatically if the feature is enabled
(CONTROL STATUS [SNOOZE] = 1) and AverageCurrent( ) is below the programmable level Sleep Current.
During SLEEP+ mode, the bq27510-G2 periodically takes data measurements and updates its data set.
However, a majority of its time is spent in an idle condition.
The bq27510-G2 exits SLEEP+ if any entry condition is broken, specifically when:
1. any communication activity with the gauge, or
2. AverageCurrent( ) rises above Sleep Current, or
3. a current in excess of IWAKE through RSENSE is detected.
BAT INSERT CHECK Mode
This mode is a halted-CPU state that occurs when an adapter, or other power source, is present to power the
bq27510-G2 (and system), yet no battery has been detected. When battery insertion is detected, a series of
initialization activities begin, which include: OCV measurement, setting the BAT_GD pin, and selecting the
appropriate battery profiles. The setting of BAT_GD pin will experience longer delay (about 2 seconds) if other
power source is not present when battery is inserted.
Some commands, issued by a system processor, can be processed while the bq27510-G2 is halted in this mode.
The gauge wakes up to process the command, then returns to the halted state awaiting battery insertion.
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