MP2602 – 28V, 1A LINEAR LI-ION BATTERY CHARGER WITH TRICKLE CHARGE
MP2602 Rev.1.3 www.MonolithicPower.com 6
1/25/2010 MPS Proprietary Information. Unauthorized Photocopy and Duplication Prohibited.
© 2010 MPS. All Rights Reserved.
BLOCK DIAGRAM
BATTERY
CHARGE
CONTROL
7
9
8
5
1
10
2
3
64
SS
ISET
IBF
NTC
R
NTC
C
SS
R
CHG
R
BF
R1
IN
BATT
CHG
ACOK
GNDEN
V
IN
C
IN
C
OUT
V
BATT
+
_
OFF ON
I
BATT
Figure 1—Functional Block Diagram
OPERATION
Input Voltage Range
The MP2602 has built-in input voltage surge
protection as high as +28V. The charger IC will
be automatically disabled when the input
voltage is lower than 2.5V or higher than 6.0V.
The open-drain pin
ACOK
is used to indicate
an input power good condition (i.e.
2.5V<V
IN
<6.0V). If the input voltage is lower
than the battery voltage, the IC is also disabled
to prevent the battery from draining.
Charge Cycle (Mode Change: Trickle -> CC-> CV)
Figure 2 below shows the typical charging
profile for the MP2602. Figure 3 shows the
typical charging procedure. For a fully depleted
battery with a terminal voltage lower than 2.6V,
the MP2602 will start with the trickle charge
(preconditioning) at 10% of the programmed full
charge current. After the battery voltage
reaches 2.6V, the charger begins charging at
the constant current of the programmed value
(I
CHG
). This is referred to as Constant Current
(CC) mode. Once the battery voltage reaches
4.2V, the charger will operate in the constant
voltage (CV) mode until the battery is fully
charged. The charge current drops during CV
mode, and the battery full indication is set when
the charge current in the CV mode is reduced
to the programmed full battery current (I
BF
).
