AAT3680 Datasheet, PDF (8/18 Pages) Advanced Analogic Technologies – Lithium-Ion Linear Battery Charge Controller

AAT3680
Lithium-Ion Linear Battery Charge Controller
Charge Status
Sleep / Charge Complete
Temp., OC, OV Fault
Battery Conditioning
Constant Current Mode
Constant Voltage Mode
Output Status
off / off / off / off
on / on / off / off
on / on / on / on
on / on / on / off
on / off / off / off
on/off
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
LED Display
on/off on/off
on/off
Figure 2: LED Display Output
High Speed Data Reporting
An optional system microcontroller interface can be
enabled by pulling the T2X pin up to 4.5V to 5.5V
during power-up sequence. The T2X pin should be
pulled high with the use of a 100kΩ resistor. If the
input supply to VP will not exceed 5.5V, then the
T2X pin may be tied directly to VP through a 100kΩ
resistor. Since this is a TTL level circuit, it may not
be pulled higher than 5.5V without risk of damage
to the device.
When the high speed data report feature is enabled,
the STAT output periods are sped up to 40µs, mak-
ing the total status word 160µs in length. See Figure
3 below.
An additional feature is the Output Status for Battery
Not Detected state. When the AAT3680 senses there
is no battery connected to the BAT pin, the STAT pin
cycles for two periods, then remains off for two periods.
When in High Speed Data Reporting, the AAT3680
will only trickle charge at the 2x trickle charge level.
This is because the TX2 pin is pull high the enable
the high speed data reporting.
A status display LED may not be not be connected
to the STAT pin when the high speed data reporting
is being utilized. If both display modes are required,
the display LED must be switched out the circuit
before the T2X pin is pulled high. Failing to do so
could cause problems with the high speed switching
control circuits internal to the AAT3680.
Charge Status
Sleep / Charge Complete
Temp., OC, OV Fault
Battery Conditioning
Constant Current Mode
Constant Voltage Mode
Output Status
HI / HI / HI / HI
LO / LO / HI / HI
LO / LO / LO / LO
LO / LO / LO / HI
LO / HI / HI / HI
STAT Level
Figure 3: Microcontroller Interface Logic Output
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3680.2003.4.0.91