LTC4015_15 Datasheet, PDF (24/76 Pages) Linear Technology – Multichemistry Buck Battery Charger Controller with Digital Telemetry System

LTC4015
Operation
Cells Selection
Number of series cells selection is made using the CELLS2,
CELLS1, and CELLS0 pins. For lithium chemistries the
LTC4015 allows charging of up to nine series cells. For
lead-acid there are only three valid selections 3, 6 or 12
cells corresponding to 6, 12, and 24V batteries respectively.
Note that number of cells multiplied by their expected
maximum cell voltage during charging cannot exceed
V_IN – 200mV. With V_IN/V_SYS limited to 35V as an upper
bound for V_BAT, at nine cells the maximum V/cell would
be 3.89V. In practice the 3.89V/cell will be lower, due to
several factors including; input ideal diode drop (V_IN – V_SYS)
and switcher max duty cycle. These pins should be hard
wired to GND(L), INTV_CC(H), or left open (Z).
NUMBER OF
CELLS
Invalid
1
2
3
4
5
6
7
8
9
Invalid
Invalid
12*
* Lead-acid only
CELLS2
L
L
L
L
L
L
L
L
L
H
H
H
H
CELLS1
L
L
H
H
L
Z
H
Z
Z
L
L
H
H
CELLS0
L
H
L
H
Z
L
Z
H
Z
L
H
L
H
Chemistry Selection
Chemistry selection is made using the CHEM1 and CHEM0
pins. These are three-state pins used by the LTC4015 to
select of one of nine chemistry specific charging algorithms.
These pins should be hard wired to GND(L), INTV_CC(H),
or left open (Z).
CHEMISTRY
Li-Ion Programmable
Li-Ion 4.2V/Cell Fixed
Li-Ion 4.1V/Cell Fixed
Li-Ion 4V/Cell Fixed
LiFePO₄ Programmable
LiFePO₄ Fixed Fast Charge
LiFePO₄ Fixed Standard Charge
Lead-Acid Fixed
Lead-Acid Programmable
CHEM1
L
H
L
Z
L
H
Z
Z
H
CHEM0
L
H
Z
L
H
Z
H
Z
L
Li-Ion/LiFePO₄ Battery Charging
It is the responsibility of the user of the LTC4015 to
consult with the battery manufacturer to determine the
recommended charging parameters for a particular battery.
Battery allowable temperature range while charging and
any required charging parameter temperature coefficients
also need to be considered.
4015f
24
For more information www.linear.com/LTC4015