Datasheet

Data Sheet ADP5065
Rev. D | Page 17 of 40
The ADP5065 also includes a number of significant features to
optimize charging and functionality, including
• Thermal regulation for maximum performance.
• USB host current-limit accuracy: ±5 %.
• Termination voltage accuracy: ±1 %.
• Battery thermistor input with automatic charger shutdown
in the event that the battery temperature exceeds limits.
(Compliant with the JEITA Li-Ion battery charging
temperature specification.)
• Offloads processor to manage external pin (TRK_EXT)
control to enable/disable trickle charging.
• Direct external pin (IIN_EXT) control of 100 mA or
500 mA input current limit.
• Optional external resistor programming input, V_WEAK_
SET, which is used for setting the V
WEAK
threshold. When
the battery reaches the V
WEAK
threshold, the ADP5065 pulls
down the SYS_EN_OK open-drain output flag. The flag can
be used to hold off system turn on until the battery is at the
minimum required level for a guaranteed system startup.
CHARGER MODES
Input Current Limit
The VINx input current limit is controlled via an internal I
2
C
ILIM register. The input current limit can also be controlled via
the IIN_EXT pin as outlined in Table 7. Any change in the I
2
C
default from 100 mA dominates over the pin setting.
Table 7. IIN_EXT Operation
IIN_EXT Function
0 100 mA input current limit or I
2
C programmed value
1 500 mA input current limit or I
2
C programmed value
(or reprogrammed I
2
C value from 100 mA default)
USB Compatibility
The ADP5065 charger provides support for the following
connections through the single connector VINx pin.
The ADP5065 features a programmable input current limit to
ensure compatibility with the requirements listed in Table 8. The
current limit defaults to 100 mA to allow compatibility with a
USB host or hub that is not configured.
The I
2
C register default is 100 mA. An I
2
C write command
to the ILIM register overrides the IIN_EXT pin and the I
2
C
register default value can be reprogrammed for alternative
requirements.
When the input current limiting feature is used, the available
input current may be too low for the charger to meet the pro-
grammed charging current, I
CHG
, and the rate of charge is
reduced. In this case, the VIN_ILIM flag is set.
When connecting voltage to VINx without having the proper
voltage level on the battery side, the HV blocking part is in a
state wherein it draws only 1.3 mA (typical) of current until the
V
IN
has reached the VIN_OK level.
Table 8. Input Current Compatibility with Standard USB Limits
Mode Standard USB Limit ADP5065 Function
USB
(China
Only)
100 mA limit for stan-
dard USB host or hub
100 mA input current limit
or I
2
C programmed value
300 mA limit for
Chinese USB
specification
300 mA input current limit
or I
2
C programmed value
USB 2.0 100 mA limit for stan-
dard USB host or hub
100 mA input current limit
or I
2
C programmed value
500 mA limit for stan-
dard USB host or hub
500 mA input current limit
or I
2
C programmed value
USB 3.0 150 mA limit for
super speed USB 3.0
host or hub
150 mA input current limit
or I
2
C programmed value
900 mA limit for
super speed, high
speed USB host or
hub charger
900 mA input current limit
or I
2
C programmed value
Dedicated
Charger
1500 mA limit for
dedicated charger or
low/full speed USB
host or hub charger
1500 mA input current limit
or I
2
C programmed value
Trickle Charge Mode
A deeply discharged Li-Ion cell may exhibit a very low cell
voltage making it unsafe to charge the cell at high current rates. The
ADP5065 charger uses a trickle charge mode to reset the battery
pack protection circuit and lift the cell voltage to a safe level for fast
charging. A cell with a voltage below V
TRK_DEAD
is charged with
the trickle mode current, I
TRK_DEAD
. During trickle charging mode,
the CHARGER_STATUS register is set.
During trickle charging, the ISO_Sx node is regulated to
V
ISO_STRK
by the dc-to-dc converter and the battery isolation FET
is off, which means the battery is isolated from the system
power supply.
Trickle charging can be controlled via the TRK_EXT external
pin (see Table 9). Note that any change in the I
2
C EN_TRK bit
dominates over the pin setting.
Table 9. TRK_EXT Operation
TRK_EXT Function
0
Trickle charge enabled
1 Trickle charge disabled
Trickle Charge Mode Timer
The duration of trickle charge mode is monitored to ensure the
battery is revived from its deeply discharged state. If trickle
charge mode runs for longer than 60 minutes without the cell
voltage reaching V
TRK_DEAD
, a fault condition is assumed and
charging stops. The fault condition is asserted on the
CHARGER_STATUS register, allowing the user to initiate
the fault recovery procedure specified in the Fault Recovery
section.