MCP73811 MICROCHIP [Microchip Technology], MCP73811 Datasheet - Page 13

• Manufacturer Part Number: MCP73811
• Description: Simple, Miniature Single-Cell, Fully Integrated Li-Ion / Li-Polymer Charge Management Controllers
• Manufacturer: MICROCHIP [Microchip Technology]

6.0
The MCP73811/2 is designed to operate in conjunction
with
applications. The MCP73811/2 provides the preferred
FIGURE 6-1:
FIGURE 6-2:
(180 mAh Battery).
FIGURE 6-3:
Thermal Regulation (1000 mAh Battery).
© 2007 Microchip Technology Inc.
6.0
5.0
4.0
3.0
2.0
1.0
0.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0
a
APPLICATIONS
host
MCP738312
V
R
MCP73812/IOT
V
R
DD
PROG
DD
PROG
= 5.2V
= 5.2V
= 2 kΩ
REGULATED
WALL CUBE
= 10 kΩ
microcontroller
Typical Application Circuit.
Typical Charge Profile
Typical Charge Profile in
Time (s)
Time (s)
or
C
IN
in
stand-alone
120
100
80
60
40
20
0
600
500
400
300
200
100
0
Li-Ion Battery Charger
4
1
V
CE
DD
MCP73812
charge algorithm for Lithium-Ion and Lithium-Polymer
cells Constant-current followed by Constant-voltage.
Figure 6-1
circuit,
accompanying charge profile.
6.1
Due to the low efficiency of linear charging, the most
important factors are thermal design and cost, which
are a direct function of the input voltage, output current
and thermal impedance between the battery charger
and the ambient cooling air. The worst-case situation is
when
Preconditioning mode to the Constant-current mode. In
this situation, the battery charger has to dissipate the
maximum power. A trade-off must be made between
the charge current, cost and thermal requirements of
the charger.
6.1.1
Selection of the external components in
crucial to the integrity and reliability of the charging
system. The following discussion is intended as a guide
for the component selection process.
6.1.1.1
The preferred fast charge current for Lithium-Ion cells
is at the 1C rate, with an absolute maximum current at
the 2C rate. For example, a 500 mAh battery pack has
a preferred fast charge current of 500 mA. Charging at
this rate provides the shortest charge cycle times
without degradation to the battery pack performance or
life.
PROG
V
V
BAT
the
SS
Application Circuit Design
while
depicts a typical stand-alone application
COMPONENT SELECTION
3
5
2
Charge Current
device
Figures 6-2
R
C
PROG
MCP73811/2
has
OUT
transitioned
+
and
-
Single
Li-Ion
Cell
6-3
DS22036A-page 13
Figure 6-1
depict
from
the
the
is