MCP738376SIMF MICROCHIP [Microchip Technology], MCP738376SIMF Datasheet - Page 17

• Manufacturer Part Number: MCP738376SIMF
• Description: Advanced Stand-Alone Li-Ion / Li-Polymer Battery Charge Management Controller with Autonomous AC-Adapter or USB-Port Source Selection
• Manufacturer: MICROCHIP [Microchip Technology]

is reconnected. If the input power is removed, the
MCP73837/8 is in Shutdown. When the input power is
reapplied, a normal start-up sequence ensues.
4.6
When the voltage at the V
regulation voltage, V
begins. The regulation voltage is factory set to 4.20V,
4.35V, 4.40V, or 4.5V with a tolerance of ± 0.5%.
4.7
The charge cycle is terminated when, during constant
voltage mode, the average charge current diminishes
below a percentage of the programmed charge current
(established with the value of the resistor connected to
the PROG pin) or the internal timer has expired. A 1 ms
filter time on the termination comparator ensures that
transient load conditions do not result in premature
charge cycle termination. The percentage or ratio of the
current is factory set. The timer period is factory set and
can be disabled. Refer to Section 1.0 “Electrical
Characteristics” for charge termination current ratio
and timer period options.
The charge current is latched off and the MCP73837/8
enters a charge complete mode.
4.8
The MCP73837/8 continuously monitors the voltage at
the V
voltage drops below the recharge threshold, another
charge cycle begins and current is once again supplied
to the battery or load. The recharge threshold is factory
set. Refer to Section 1.0 “Electrical Characteristics”
for recharge threshold options.
© 2007 Microchip Technology Inc.
Note:
BAT
Constant Voltage Mode
Charge Termination
Automatic Recharge
pin in the charge complete mode. If the
Charge
recharge features avoid constant charging
Li-Ion batteries to prolong the life of Li-Ion
batteries while keeping their capacity at
healthy level.
REG
termination
, constant voltage regulation
BAT
pin reaches the
and
automatic
4.9
The MCP73837/8 limits the charge current based on
the die temperature. The thermal regulation optimizes
the charge cycle time while maintaining device
reliability.
the MCP73837/8. Refer to Section 1.0 “Electrical
Characteristics” for thermal package resistances and
Section 6.1.1.2
calculating power dissipation.
.
FIGURE 4-2:
4.10
The MCP73837/8 suspends charge if the die
temperature exceeds 150°C. Charging will resume
when
approximately 10°C. The thermal shutdown is a
secondary safety feature in the event that there is a
failure within the thermal regulation circuitry.
1200
1100
1000
900
800
700
600
500
400
300
200
100
0
25
the
Thermal Regulation
Thermal Shutdown
Figure 4-2
35
45
die
55
“Thermal
Junction Temperature (°C)
65
temperature
depicts the thermal regulation for
MCP73837/8
Thermal Regulation.
75
85
95 105 115 125 135 145 155
Considerations”
has
DS22071A-page 17
R
PROG
cooled
= 1 kΩ
for
by