Marine Instruments User Manual

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ExitFromSLEEP
| AverageCurrent () | >SleepCurrent
OR
CurrentisDetectedaboveI
WAKE
EntryToHIBERNATE
Hosthasset ControlStatus
[HIBERNATE]=1
OR
V
CELL
< HibernateVoltage
Fuel gauginganddata
updatedevery 1s,
I
CC
= Normal
NORMAL
Fuel gauginganddata
updated every60seconds
I
CC
= Sleep
SLEEP
Disableallbq8032
subcircuitsexceptGPIO.
Set /BAD_GDto “high”
status
I
CC
= Hibernate
HIBERNATE
EntrytoSLEEP
OperationConfiguration[SLEEP]=1
AND
|AverageCurrent()|
≤ SleepCurrent
Wakeup From HIBERNATE
Communication Activity
AND
CommaddressisNOT forbq27500/1
ExitFrom HIBERNATE
(Communication Activity
AND
Commaddressisforbq27500/1)
OR
BatteryRemoved
(ControlStatus
[ HIBERNATE] issetto 0.
POR
Checkforbatteryinsertion
fromHALT state
.
Nogauging
I
CC
= Sleep
BAT INSERT CHECK
EntrytoNORMAL
Flags [ BAT_DET]=1
ExitFromNORMAL
Flags [ BAT_DET]=0
ExitFrom SLEEP
Flags [BAT_DET]=0
Flags [BAT_DET
]=0
5.7.4 HIBERNATE MODE
bq27500
bq27501
System-Side Impedance Track™ Fuel Gauge
SLUS785 – SEPTEMBER 2007
Figure 5-2. Power Mode Diagram
HIBERNATE mode should be used when the system equipment needs to enter a very low-power state,
and minimal gauge power consumption is required. This mode is ideal when a system equipment is set to
its own SLEEP, HIBERNATE, or SHUTDOWN modes.
To enter HIBERNATE mode, either the system must set the [HIBERNATE] bit of the CONTROL STATUS
register OR the cell voltage must fall below Hibernate Voltage. The gauge will remain in HIBERNATE
mode until the battery is removed, or the system issues a direct I
2
C command to the gauge. I
2
C
Communication that is not directed to the gauge will not wake the gauge.
It is important that BAT_GD be set to disable status (no battery charging/discharging). This prevents a
charger application from inadvertently charging the battery before an OCV reading can be taken. It is the
system’s responsibility to wake the bq27500/1 after it has gone into HIBERNATE mode. After waking, the
gauge can proceed with the initialization of the battery information (OCV, profile selection, etc.)
FUNCTIONAL DESCRIPTION28 Submit Documentation Feedback