AAT3686-1 Advanced Analog Technology, Inc., AAT3686-1 Datasheet - Page 17

• Manufacturer Part Number: AAT3686-1
• Description: USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger
• Manufacturer: Advanced Analog Technology, Inc.

BatteryManager
Digital Charge Status Reporting
The AAT3686 has a comprehensive digital data reporting
system by use of the DATA pin feature. This function can
provide detailed information regarding the status of the
charging system. The DATA pin is a bi-directional port
which will read back a series of data pulses when the
system microcontroller asserts a request pulse. This sin-
gle strobe request protocol will invoke one of 22 possible
return pulse counts which the microcontroller can look up
based on the serial report table shown in Table 4.
The DATA pin function is active low and should normally
be pulled high to V
pulled high to the same level as the high state for the
logic I/O port on the system microcontroller. In order for
the DATA pin control circuit to generate clean, sharp
3686.2007.12.1.11
Number
10
11
12
1
2
3
4
5
6
7
8
9
DATA Report Status
Chip Over-Temperature Shutdown
Battery Temperature Fault
Over-Voltage Turn Off
Not Used
ADP Watchdog Time-Out in Battery Condition Mode
ADP Battery Condition Mode
ADP Watchdog Time-Out in Constant Current Mode
ADP Thermal Loop Regulation in Constant Current
Mode
ADP Constant Current Mode
ADP Watchdog Time-Out in Constant Voltage Mode
ADP Constant Voltage Mode
ADP End of Charging
AAT3686
Control
Status
ADP
OUT
or V
TM
IN
USB
. This data line may also be
USB Port/AC Adapter Lithium-Ion/Polymer Battery Charger
Figure 4: Data Pin Application Circuit.
Table 4: Serial Data Report Table.
DATA Pin
w w w . a n a l o g i c t e c h . c o m
1.8V to 5.0V
R
Number
PULL_UP
edges for the data output and to maintain the integrity
of the data timing for the system, the pull-up resistor on
the data line should be low enough in value so that the
DATA signal returns to the high state without delay. If
too small a pull-up resistor is used, the strobe pulse
from the system microcontroller could exceed the maxi-
mum pulse time and the DATA output control could issue
false status reports. A 1.5kΩ resistor is recommended
when pulling the DATA pin high to 5.0V on either V
V
level less than 5.0V, the pull-up resistor can be calcu-
lated based on a recommended minimum pull-up cur-
rent of 3mA. Use the following formula:
USB
13
14
15
16
17
18
19
20
21
22
23
inputs. If the data line is pulled high to a voltage
DATA Report Status
USBH Battery Condition Mode
USBH Charge Reduction in Constant Current Mode
USBH Constant Current Mode
USBH Constant Voltage Mode
USBH End of Charging
USBL Battery Condition Mode
USBL Charge End of Charging Reduction in
Constant Current Mode
USBL Constant Current Mode
USBL Constant Voltage Mode
USBL End of Charging
Data Report Error
R
GPIO
PRODUCT DATASHEET
PULL-UP
≤
V
AAT3686
µP GPIO
3mA
PULL-UP
IN
Port
OUT
ADP
17
or