LTC4015_15 Datasheet, PDF (25/76 Pages) Linear Technology – Multichemistry Buck Battery Charger Controller with Digital Telemetry System

LTC4015
Operation
Li-Ion/Charging Parameters
Table 5 shows Li-Ion charging parameters. For Li-Ion
programmable, defaults values are shown.
Bold parameters are I²C programmable in Li-Ion
programmable mode only. ICHARGE_TARGET and
VCHARGE_SETTING values are at 25°C if JEITA is en-
abled¹. Shown in Figure 3 is an example of a Li-Ion battery
charging profile. Shown in Table 6 are the Li-Ion program-
mable I²C configurable charging parameters.
Table 5. Li-Ion Charging Parameters
CHARGING ICHARGE_ V_CHARGE
CV TIMER
ALGORITHM TARGET (PER CELL) TERM ENABLE
MAX CV
TIME
Li-Ion
Programmable
Li-Ion 4.2V/cell
Fixed
Li-Ion 4.1V/cell
Fixed
Li-Ion 4V/cell
Fixed
32mV/
R_SNSB1
32mV/
R_SNSB1
32mV/
R_SNSB1
32mV/
R_SNSB1
4.20¹
4.20¹
4.10¹
4.00¹
Yes
4 Hours
Yes
4 Hours
Yes
4 Hours
Yes
4 Hours
C/x TERM
ENABLE
No
C/x
THRESH
10%
JEITA
Y
MAX
CHARGE
TIME
18 Hrs
LOW BAT
PRECHARGE
CURRENT
~10%²
LOW BAT
THRESHOLD
(PER CELL)
2.9V
No
–
Y
18 Hrs
~10%²
2.9V
No
–
Y
18 Hrs
~10%²
2.9V
No
–
Y
18 Hrs
~10%²
2.9V
Table 6. Li-Ion Programmable I²C Configurable Parameters
PROGRAMMABLE MODE
PARAMETER
RANGE
BITS RESOLUTION
ICHARGE_TARGET¹
VCHARGE_SETTING¹
1mV to 32mV/ 5
R_SNSB
3.8125V to
5
4.2V/Cell
1mV/R_SNSB
12.5mV
MAX_CV_TIME
0 to 65535
16
1 Second
en_jeita
0, 1
1
1 = Enable
en_c_over_x_term
0, 1
1
1 = Enable
C_OVER_X_THRESHOLD 0mV to 32mV/ 16
R_SNSB
1.465µV/R_SNSB
MAX_CHARGE_TIME
0 to 65535
16
1 Second
Notes
1) When JEITA is enabled (en_jeita=1), ICHARGE_TARGET and
VCHARGE_SETTING are controlled by the JEITA temperature controlled
charging algorithm, as described in the descriptions for ICHARGE_
JEITA_n and VCHARGE_JEITA_n.
2) Precharge current is 10% of ICHARGE_TARGET, rounded down to
the next LSB.
4.5 _{CC_CV/CC}
4.0
TEXT INDICATES VALUES REPORTED IN REGISTERS:
CHARGER_STATE/CHARGE_STATUS
CC_CV/CV
12
3.5
3.0
9
V_BAT
2.5
I_CHG
2.0
6
4HOUR CV TIMER
1.5
TERMINATION
1.0
3
0.5
0
0
0
1
2
3
4
5
6
TIME (hr)
4015 F03
Figure 3. Li-Ion 4.2V/Cell Fixed Charging Profile
For more information www.linear.com/LTC4015
4015f
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