ACT81460
Rev 1.0, 18-Dec-2018
Fast Charge Current set by ISET Pin = 1C
Optional
(full charge current
from 0 – 10C)
0.5C
Optional
(stop charge at 45C)
Maximum Charge Voltage:
VTERM[4:0]
Typical 4.35V
VTERM -100mV
VTERM -150mV
0°C
10°C
45°C
50°C
60°C
JEITA Charging Profile
Figure 5: NTC Temperature Thresholds
actual system resistance, and ICHG is the actual charg-
ing current.
Battery Path Impedance (Cord) Compensation
The ACT81460 includes a Battery Path Impedance
Compensation (Cord Comp) feature that speeds the
charging cycle. This feature compensates for system
level voltage drops due to PCB, connector, wiring re-
sistances, and battery pack current sense resistances.
As an example, if the actual system resistance is
320mΩ, select CORD_COMP_SETTING = 300mΩ. If
ICHG = 800mA, and VTERM = 4.2V, the charger stays
in fast charge mode until the battery voltage reaches
4.2V + 800mA*300mΩ = 4.44V.
These voltage drops effectively reduce the voltage at
the battery. This results in the charger reaching the con-
stant voltage portion of the charge cycle too soon. The
Cord Comp feature allows the charger to stay in the
constant current mode longer, which reduces the charg-
ing time.
It is important to note that the actual battery voltage
never exceeds 4.2V because of the system level volt-
age drops.
It is also important to select a Cord Comp value that is
LOWER than the actual system resistance. This en-
sures that the battery voltage never exceeds the
VTERM voltage.
The ACT81460 allows the user to compensate for the
system level resistances by increasing the battery ter-
mination voltage, VTERM as a function of charge cur-
rent according to the equation below. This feature is im-
plemented with the I2C register: CORD_COMP_SET-
TING[2:0]. This register sets the system level resistance
that is being accounted for. It can be programmed be-
tween 0mΩ and 420mΩ. Setting the value to 0mΩ ef-
fectively disables Cord Comp. The user should always
pick a Cord Comp value lower than the actual system
level resistance. The following equation shows the Cord
Comp voltage, VCOMP.
The charger is capable of status and fault monitoring
and is designed to work with a host of host processor
via interrupt generation and status and fault reporting.
Host processor interrupts shall be generated for any
change in battery charging state:
1) JEITA temp threshold crossed
2) Battery voltage low
3) Battery removed/inserted
4) Charge source plugged/unplugged
ꢅ
ꢪꢐꢯꢰ
ꢀ ꢎꢱꢣꢲ_ꢎꢱꢮꢢ_ꢳꢤꢭꢭꢁꢴꢵ ∗ ꢁꢪꢫꢬ
5) Charge condition / state change – Precondition, fast
charge, top off and end of charge reached.
Where VCORD is the increase in VTERM,
CORD_COMP_SETTING is nearest Cord Comp to the
Innovative PowerTM
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53
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