Specifications

Wireless CPU
®
Q24 Series
Interfaces
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prior written agreement.
WM_PRJ_Q24NG_PTS_001-004
January 16, 2007
Ni-Cd / Ni-Mh charging process
Charger connected: CHG_IN =VBATT+0.5V
VBATT Operating
system
Charging status Switching transistor
(T)
VBATT<2V8 Not activated Trickle charge Open
2V8<VBATT<3V2 Not activated Pre-charging 50mA typ cross the
switching transistor
3V2<VBATT
VBATT<BattLevelMin
Activated Charging process is
automatically started
Open (T2)/Close (T1)
periodically
Charging process
running
Open (T2)/Close (T1)
periodically
Activated
Charging process not
activated
VBATT is monitored
periodically (T3)
BattLevelMin<VBATT
VBATT<BattLevelMax
Deactivated Trickle charge Open
>=BattLevelMax Activated Charging process is
ended
Open
The graph below summarizes the charging process (charge and discharge).
Note:
A charger is connected to the CHG_IN pin of the Wireless CPU
®
.
Figure 8: Ni-Cd / Ni-Mh charging waveform
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