Q2686 Wavecom, Q2686 Datasheet - Page 49

• Manufacturer Part Number: Q2686
• Description: Wireless CPU
• Manufacturer: Wavecom

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3.13
The Q2686 Wireless CPU
algorithms and one hardware charging mode (pre-charging) for 3 battery
technologies:
The two algorithms control a switch, which connects the CHG-IN signal to the
VBATT signal. The algorithm controls the frequency and the connected time of
the switching. During the charging procedure, battery charging level is
controlled and when the Li-Ion algorithm is used, battery temperature is
monitored via the BAT-TEMP ADC input.
One more charging procedure is provided by the Q2686 Wireless CPU
called “Pre-charging” mode, but is a special charging mode as it is activated
only when the Wireless CPU
hardware. The purpose of this charging mode is to avoid battery damage by
preventing the battery from being discharged to below the minimum battery
level.
3.13.1 Ni-Cd / Ni-Mh Charging Algorithm
To charge the battery, the algorithm measures battery level when the switch is
open (T2) and charges the battery by closing the switch (T3). When the battery
is charged (battery voltage has reached BattLevelMax) the switch is open for
time T3.
The battery level is monitored by the software (but not temperature)
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged without
prior written agreement.
WM_PRJ_Q2686_PTS_001-007
Note: T1,T2,T3 and BattLevelMax may be configured by AT command.
Switch State
Battery Level
•
•
•
Ni-Cd
Ni-Mh (Nickel-Métal Hydrure) with algorithm 0
Li-Ion
Electrical characteristics of Ni-Cd / Ni-Mh battery timing charge
Battery Charging Interface
closed
opened
Parameter
T1
T2
T3
(Nickel-Cadmium) with algorithm 0
(Lithium-Ion) with algorithm 1
T2
confidential ©
Figure 5: Ni-Cd / Ni-Mh charging waveform
BattLevelMax
T1
®
®
supports one battery charging circuit, two
is OFF. Control is thus only performed by the
Min
Typ
0.1
1
5
Q2686 Wireless CPU
T3
Max
Interfaces
®
. This is
Unit
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March 6, 2007
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