Datasheet

Data Sheet ADP5065
Rev. D | Page 21 of 40
BATTERY PACK TEMPERATURE SENSING
Battery Thermistor Input
The ADP5065 charger features battery pack temperature
sensing that precludes charging when the battery pack
temperature is outside the specified range. The THR pin
provides an on and off switching current source, which should
be connected directly to the battery pack thermistor terminal.
The activation interval of the THR current source is 167 ms.
The battery pack temperature sensing can be controlled by
I
2
C using the conditions shown in Table 10. Note that the
I
2
C register default setting for EN_THR (Register 0x07) is
0 = temperature sensing off.
Table 10. THR Input Function
Conditions
THR Function
VINx V
ISO_B
Open or V
IN
= 0 V to 4.0 V <2.5 V Off
Open or V
IN
= 0 V to 4.0 V >2.5 V Off, controlled by I
2
C
4.0 V to 5.5 V Don't care Always on
If the battery pack thermistor is not connected directly to the
ADP5065 THR pin, a 10 kΩ (tolerance ±20%) dummy resistor
must be connected between the THR input and GND. Leaving
the THR pin open results in a false detection of the battery
temperature being <0°C and charging is disabled.
The ADP5065 charger monitors the voltage in the THR pin and
suspends charging if the current is outside the range of less than
0°C or greater than 60°C. For temperatures greater than 0°C,
the THR_STATUS register is set accordingly, and for temperatures
lower than 60°C, the THR_STATUS register is, likewise, set
accordingly.
The ADP5065 charger is designed for use with an NTC
thermistor in the battery pack with a nominal room tempera-
ture value of either 10 kΩ at 25°C or 100 kΩ at 25°C, which is
selected by a fuse.
The ADP5065 charger is designed for use with an NTC
thermistor in the battery pack with a temperature coefficient
curve (beta). Fuse-selectable beta programming is supported by
eight steps covering a range from 3150 to 4400 (see Table 34).
JEITA Li-Ion Battery Temperature Charging Specification
The ADP5065 is compliant with the JEITA Li-Ion battery
charging temperature specifications as outlined in Table 11.
The JEITA function can be enabled via the I
2
C interface. When
the ADP5065 detects a JEITA cool condition, charging current
is reduced according to Table 12.
When the ADP5065 identifies a hot or cold battery condition,
the ADP5065 takes the following actions:
• Stops charging the battery.
• Connects/enables the battery isolation FET such that the
system power supply node is connected to the battery.
Table 11. JEITA Li-Ion Battery Charging Specification Defaults
Parameter Symbol Conditions Min Max Unit
JEITA Cold Temperature Limits I
JEITA_COLD
No battery charging occurs. 0 °C
JEITA Cool Temperature Limits I
JEITA_COOL
Battery charging occurs at approximately 50% of programmed level.
See Table 12 for specific charging current reduction levels.
0 10 °C
JEITA Typical Temperature Limits I
JEITA_TYP
Normal battery charging occurs at default/programmed levels. 10 45 °C
JEITA Warm Temperature Limits I
JEITA_WARM
Battery termination voltage (V
TRM
) is reduced by 100 mV from
programmed value.
45 60 °C
JEITA Hot Temperature Limits I
JEITA_HOT
No battery charging occurs. 60 °C
Table 12. JEITA Reduced Charge Current Levels
JEITA Cool Temperature Limit—Reduced Charge Current Levels
ICHG[2:0] (Default) ICHG JEITA (mA)
000 = 550 mA 250
001 = 650 mA 300
010 = 750 mA 350
011 = 850 mA 400
100 = 950 mA 450
101 = 1050 mA 500
110 = 1150 mA 550
111 = 1250 mA 600