User's Manual

Wireless CPU Q24 Series
Interfaces
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WM_PRJ_Q24NG_PTS_001-003
November 2006
Note:
A charger is connected to the CHG_IN pin of the Wireless CPU.
Figure 8: Ni-Cd / Ni-Mh charging waveform
3.14.4 Li-Ion Charging Algorithm
During the charging process of a Li-Ion battery, it is required to tune parameters
embedded in the Wireless CPU operating system:
AT+WBCM=<Mode>,<ChargeInd>,<TdeltaTemp>,<BattLevelMax>,
<BattLevelMin>, <MaxVoltPulse>,
<MaxBatteryTemp>,<MinBatteryTemp>,<Charging_Current>, <DedicatedVoltStart>,
<Battery_Pulse_Charging_Timeout>, <Battery_Fast_Charging_Timeout>,
<TPulseOutCharge>, <BattIntRes>, <BattChangeLevel> (See the AT command
Interface Guide
[5]).
Caution:
The parameters need to be tuned according to the battery specifications.
The main parameters to be tuned are:
Parameters related to time:
• BatteryFastChargingTimeout: Maximum duration of the fast charging period.
(T1)
• BatteryPulseChargingTimeout: Maximum duration of the charging pulse
period.(T2)
• TPulseOutCharge: Monitoring time of the VBATT voltage when charging
process is not activated(T3)
Parameters related to voltage:
• BattLevelMin: Minimum VBATT voltage allowed by the battery (>3.2V)
• BattLevelMax: Maximum VBATT voltage allowed by the battery (<4.5V)
• DedicatedVoltStart: Pulse charging is started above this threshold voltage
Parameter related to charging current:
• ChargingCurrent: Charging current delivered by the charger
VBATT=BattLevelMax:
Charging process
ended
VBATT=BattLevelMin:
Charging process
automatically started
T3
T3
T2 T2
T1 T1 T1
T2
Switching transistor:
Closed
Open
Time
VBAT
T
BattLevelMax
BattLevelMin
Time