LX2202CLQ-TR MICROSEMI [Microsemi Corporation], LX2202CLQ-TR Datasheet - Page 9

• Manufacturer Part Number: LX2202CLQ-TR
• Description: TM 2A Li-Ion Linear Charger and Power Control
• Manufacturer: MICROSEMI [Microsemi Corporation]

Copyright © 2004
Rev. 1.0a, 2006-02-09
G
Ion battery using two steps: a constant current step
followed by a constant voltage step. The basic charger
function uses the VDD pins as an input and BAT pins as
the output. The LX2202 charger has a programmable
maximum current (programmable by the resistor value
between pin CCP to GND) which is the maximum
charging current during the Constant Current Mode of the
charging profile. The low dropout of the pass element
allows the battery to be charged from a loosely regulated
power supply. In the Constant Voltage Mode, the battery
terminal voltage can be regulated to 4.1V or 4.2V by
strapping the VM pin to VDD or GND, respectively. The
charger will terminate constant voltage charging once the
current drops below the minimum current setting
(programmable by the resistor value between pin CTP to
GND).
thermal regulation loop that will throttle back the charging
current to prevent the internal die temperature from
exceeding 150ºC. This feature prevents damage to the
system board when the IC exceeds its thermal temperature.
C
deeply discharged and have a terminal voltage less than
60% of the constant voltage level. The conditioning current
is 5% of the CCP programmable constant current level
(except where it might be limited in the USB states). Once
the battery terminal voltage exceeds the 60% level, the full
constant current level is applied (unless charging current is
limited by one of the other charger control loops).
C
the LX2202 turns off the pass element once the battery has
been fully charged. The charge termination state occurs at
the end of constant voltage mode. The charge status
changes state when charging is completed.
URRENT
HARGE
ENERAL
The LX2202 is designed to charge a single cell Lithium
The LX2202 has an integrated thermostat with a linear
A conditioning current is applied to batteries that are
To increase system battery life and avoid float charging,
TM
T
D
C
ERMINATION
ESCRIPTION
HARGE
M
ODE
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: [phone]
M
ODE
T H E O R Y O F O P E R A T I O N
Integrated Products Division
®
Microsemi
2A Li-Ion Linear Charger and Power Control
T
power remains applied, the LX2202 enters a Voltage
Monitoring mode. In this mode the LX2202 monitors the
battery terminal voltage and applies a top off charge if the
battery voltage drops by more than 3% of full scale. This
feature is especially important for charging systems in
equipment where usage is infrequent.
USB C
USB specifications – the Low Power Peripheral (100mA)
and High Power Peripherals (500mA). VID1 logic input
selects USB charge currents.
current flowing from the USB terminal to the VDD
terminal; then it limits the USB current by reducing the
current flowing from V
D
VID0 is used to enable discharge mode enable.
system load is connected to VDD. The input power is
connected to VDD through an external diode. When the
input power is removed, the battery current flows from
V
in a discharge mode configuration with both AC adapter
and USB inputs. The USB input is diode ORed to the
VDD pin and uses a MOSFET to reduce the diode drop
across the ORing diode. The LX2202 provides a signal
“PSW” to control the MOSFET for charge and discharge
modes. When both AC and USB power are applied the
PSW signal is overridden by the AC adapter diode and the
MOSFET is turned off
UNDER VOLTAGE LOCK OUT
monitors the VDD terminal and prevents the battery
charger from entering charge mode if the VDD terminal is
less than 3.6V (nominal).
OP
ISCHARGE
BAT
The LX2202 has an under voltage lock-out feature that
Once the charger has completed a charge cycle, if
The LX2202 is fully compliant with, and supports, the
O
to VDD. The circuit of Figure 3 shows the LX2202
FF
HARGE
C
HARGE
M
P
M
ODE
RODUCTION
ODE
M
ODE
DD
to V
D
ATA
BAT
The LX2202 senses the
.
S
HEET
LX2202
The
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