AAT3680 Advanced Analogic Technologies, AAT3680 Datasheet - Page 9

• Manufacturer Part Number: AAT3680
• Description: Lithium-Ion Linear Battery Charge Controller
• Manufacturer: Advanced Analogic Technologies

Protection Circuitry
The AAT3680 is truly a highly integrated battery
management system IC including several protection
features. In addition to battery temperature monitor-
ing, the IC constantly monitors for over-current and
over-voltage conditions; if an over-current situation
occurs, the AAT3680 latches off the pass device to
prevent damage to the battery or the system, and
enters shutdown mode until the over-current event is
terminated.
An over voltage condition is defined as a condition
where the voltage on the BAT pin exceeds the max-
imum battery charge voltage. If an over-voltage con-
dition occurs, the IC turns off the pass device until
voltage on the BAT pin drops below the maximum
3680.2003.4.0.91
STAT
VP
Voltage Threshold
and Termination
Preconditioning
Output Charge
Trickle Charge
Voltage (V
(I
Regulation
CHARGE(REG)
Threshold
R
C1
4.7 F
High Speed Data Reporting Application Schematic
SENSE
0.2
Current
(V
MIN
CH
)
)
)
(Trickle Charge)
Preconditioning
100k
R2
FZT788B
Phase
Figure 4: Typical Charge Profile
Q1
2.5k
R1
Lithium-Ion Linear Battery Charge Controller
Constant Current
DRV
CSI
VP
VSS
Phase
AAT3680
STAT
BAT
TX2
TS
battery charge constant voltage threshold.
AAT3680 will resume normal operation after the
over-current or over voltage condition is removed.
During an over-current or over-voltage event, the
STAT will report a FAULT signal.
In the event of a battery over-temperature condition,
the IC will turn off the pass device and report a
FAULT signal on the STAT pin. After the system
recovers from a temperature fault, the IC will resume
operation in the 1X trickle charge mode to prevent
damage to the system in the event a defective bat-
tery is placed under charge. Once the battery volt-
age rises above the trickle charge to constant cur-
rent charge threshold, the IC will resume the con-
stant current mode.
Constant Voltage
100k
Phase
VP
RT1
RT2
C2
10 F
C3
0.1 F
BATT+
BATT-
TEMP
Battery
Pack
AAT3680
The
9