MCP73863-I/ML Microchip Technology, MCP73863-I/ML Datasheet - Page 20

• Manufacturer Part Number: MCP73863-I/ML
• Description: IC,Battery Management,LLCC,16PIN,PLASTIC
• Manufacturer: Microchip Technology

Specifications of MCP73863-I/ML

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion), Lithium-Polymer (Li-Pol)
• Voltage - Supply: 4.5 V ~ 12 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-QFN
• Output Voltage: 4.1 V, 4.2 V
• Output Current: 1200 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

MCP73861/2/3/4
FIGURE 6-3:
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.
DS21893D-page 20
the
Application Circuit Design
COMPONENT SELECTION
Regulation
Voltage
(V
Regulation
Current
(I
Transition
Threshold
(V
Precondition
Current
(I
Termination
Current
(I
REG
PREG
TERM
Current Programming Resistor
(R
device
REG
PTH
PROG
)
)
)
)
)
)
Typical Charge Profile in Thermal Regulation.
has
Preconditioning
Mode
Precondition
Safety Timer
transitioned
Figure 6-1
from
Charge
Voltage
Fast Charge
Safety Timer
Constant-Current
Mode
the
is
Elapsed Time
Termination Timer
1200 mA is the maximum charge current obtainable
from the MCP7386X. For this situation, the PROG input
should be connected directly to V
6.1.1.2
The worst-case power dissipation in the battery char-
ger occurs when the input voltage is at the maximum
and
Preconditioning mode to the Constant-current mode. In
this case, the power dissipation is:
Where:
I
V
PowerDissipation
V
REGMAX
PTHMIN
DDMAX
the
device
Thermal Considerations
= the maximum input voltage
= the maximum fast charge current
= the minimum transition threshold
Charge
Current
Constant-Voltage
Mode
voltage
=
(
V
has
DDMAX
© 2008 Microchip Technology Inc.
transitioned
–
V
PTHMIN
SS
.
)
×
I
REGMAX
from
the