BQ27505YZGR-J4

Manufacturer Part NumberBQ27505YZGR-J4
DescriptionIC BATT FUEL GAUGE LIION 12DSBGA
ManufacturerTexas Instruments
SeriesImpedance Track™
BQ27505YZGR-J4 datasheet
 


Specifications of BQ27505YZGR-J4

FunctionFuel, Gas Gauge/MonitorBattery TypeLithium-Ion (Li-Ion)
Voltage - Supply2.4 V ~ 2.6 VOperating Temperature-40°C ~ 85°C
Mounting TypeSurface MountPackage / Case12-UFBGA, WLCSP
Lead Free Status / RoHS StatusLead free / RoHS Compliant  
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5.3.4 Power Path Control with the BAT_GD Pin
The bq27505-J4 must operate in conjunction with other electronics in a system appliance, such as
chargers or other ICs and application circuits that draw appreciable power. After a battery is inserted into
the system, there should be no charging current or a discharging current higher than C/20, so that an
accurate OCV can be read. The OCV is used for helping determine which battery profile to use, as it
constitutes part of the battery impedance measurement.
When a battery is inserted into a system, the Impedance Track™ algorithm requires that no charging of
the battery takes place and that any discharge is limited to less than C/20–these conditions are sufficient
for the fuel gauge to take an accurate OCV reading. To disable these functions, the /BAT_GD pin is
merely negated from the default setting. Once an OCV reading has be made, the /BAT_GD pin is
asserted, thereby enabling battery charging and regular discharge of the battery. The Operation
Configuration [BATG_POL] bit can be used to set the polarity of the battery good signal, should the
default configuration need to be changed.
Exit From HIBERNATE
Battery Removed
Exit From HIBERNATE
Communication Activity
AND Comm address is for bq27505
bq27505 clears Control Status
[HIBERNATE ] = 0
Recommend Host also set Control
Status [HIBERNATE] = 0
HIBERNATE
Wakeup From HIBERNATE
Communication Activity
AND
Comm address is NOT for bq27505
Disable all bq27505
subcircuits except GPIO.
Negate /BAT_GD
Operation Configuration[SLEEP] = 1
| AverageCurrent( ) | ≤ Sleep Current
Exit From WAIT_HIBERNATE
Cell relaxed
WAIT_HIBERNATE
AND
| AverageCurrent() | < Hibernate
Current
OR
Fuel gauging and data
Cell relaxed
updated every 20 seconds
AND
V
< Hibernate Voltage
/BAT_GD unchanged
CELL
System Shutdown
Figure 5-1
details how the /BAT_GD pin functions in the context of battery insertion and removal, as well
as NORMAL vs. SLEEP modes.
Copyright © 2009, Texas Instruments Incorporated
POR
BAT INSERT CHECK
Check for battery insertion
from HALT state.
No gauging
Flags [BAT _DET] = 0
Entry to NORMAL
Exit From NORMAL
Flags [BAT _DET] = 1
Flags [BAT _DET] = 0
NORMAL
Fuel gauging and data
updated every 1s
Entry to SLEEP+
Operation Configuration[SLEEP] = 1
AND
Control Status[SNOOZE] = 1
AND
| AverageCurrent( ) | ≤ Sleep Current
Entry to SLEEP
AND
SLEEP+
AND
Control Status[SNOOZE] = 0
Fuel gauging and data
updated every 20 seconds
Both LFO and HFO are ON
Entry to SLEEP+
Control Status[SNOOZE] = 0
SLEEP
Fuel gauging and data
Exit From WAIT _HIBERNATE
updated every 20 seconds
(LFO ON and HFO OFF)
Host must set Control Status
[HIBERNATE ] = 0
AND
V
> Hibernate Voltage
CELL
Exit From SLEEP
(Host has set Control Status
[HIBERNATE] = 1
V
< Hibernate Voltage
CELL
Figure 5-1. Power Mode Diagram
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bq27505-J4
SLVSA40 – DECEMBER 2009
Exit From SLEEP
Flags [BAT_DET] = 0
Exit From SLEEP
| AverageCurrent( ) | > Sleep Current
OR
Current is Detected above I
WAKE
Exit From SLEEP+
Any communication to the gauge
OR
| AverageCurrent( ) | > Sleep Current
OR
Current is Detected above I
WAKE
Entry to SLEEP+
Control Status[SNOOZE] = 1
OR
FUNCTIONAL DESCRIPTION
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