NSC LM3622MX-8.4, LM3622MX-8.2, LM3622MX-4.2, LM3622MX-4.1, LM3622M-4.1 Datasheet
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LM3622
Lithium-Ion Battery Charger Controller
LM3622 Lithium-Ion Battery Charger Controller
February 2000
General Description
The LM3622 is a charge controller for Lithium-Ion batteries.
This monolithic integrated circuit accurately controls an external passtransistor for precision Lithium-Ion battery charging. The LM3622 provides a constant voltage or constant
current (CVCC) configuration that changes, as necessary,to
optimally charge lithium-ion battery cells. Voltage charging
versions (4.1V, 4.2V,8.2V, and 8.4V) are available for one or
two cell battery packs and for coke or graphite anode battery
chemistry.
The LM3622 accepts input voltages from 4.5V to 24V. Controller accuracy over temperature is
±
and
50mV/cell for the standard grade. No precision external resistors are required. Furthermore, the LM3622’sproprietary output voltage sensing circuit drains less than 200nA
from the battery when the input source is disconnected.
The LM3622 circuitry includes functions for regulating the
charge voltage with a temperature compensated bandgap
reference and regulating the current with an external sense
resistor. The internal bandgap insures excellent controller
performance over the operating temperature and input supply range.
The LM3622 can sink 15mA minimum at the EXT pin to drive
the base of an external PNP pass transistor. It also has
±
30mV/cell for A grade
Typical Application
low-voltage battery threshold circuitry that removes thisdrive
when the cell voltage drops below a preset limit. The LV
pin programs this threshold voltage to either 2.7V/cell or
2.15V/cell. The low-voltage detection, which is a user enabled feature, provides an output signal that can be used to
enable a ″wake up charge″ source automatically to precondition a deeply discharged pack.
The LM3622 is available in a standard 8-lead SOIC surface
mount package.
SEL
Features
n Versions for charging of 1 cell (4.1V or 4.2V) or 2 cells
(8.2V or 8.4V)
n Versions for coke or graphite anode
n Precision (
n Wide input range: 4.5V-24V
n Low battery drain leakage: 200nA
n 15 mA available to drive low cost PNP
±
30mV/cell) end-of-charge control
Applications
n Cellular phone cradle charger
n PDA/Notebook cradle charger
n Camcorder cradle charger
DS100974-1
© 2000 National Semiconductor Corporation DS100974 www.national.com
Connection Diagram
LM3622
8-Lead Surface Mount Package
DS100974-2
Refer to the Ordering Information Table in this Datasheet for Specific Part Number
See NS Package M08A
Pin Description
Pin No. Name I/O Description
1LV
2LV
SEL
ENB
3LV
4 GND Ground IC common.
5 CS Input Input for battery charge current and battery negative-terminal voltage sensing.
6 CEL Input Battery positive-terminal voltage sensing.
7 EXT Output Output of the controller for driving a PNP transistor or P-MOSFET. The controller
8V
CC
Input Low-voltage detection threshold Select. The threshold is 2.15V/cell when this pin is
pulled low to GND and 2.70V/cell when it is pulled up to V
sensed between CEL and CS pins.
Input Low-voltage detection Enable. The low-voltage detection is enabled when this pin is
pulled Low to GND. Pulling this pin HIGH to V
Output Output of the low-voltage detection. This pin is a NPN open-collector output that
goes to low impedance state when LV
below the threshold set by LV
voltage when LV
is pulled HIGH to VCC. LV can be used for turning on a low
ENB
. LV stays in HIGH impedance state at any battery
SEL
current source to recondition a deeply depleted battery.
Battery charging current is sensed through an external resistor, R
between the battery’s negative terminal and GND. The maximum charge current is
regulated to a value of 100mV/R
.
CS
modulates the current sinking into this pin to control the regulation of either the
charge current or the battery voltage.
Power Supply IC power supply
. The battery voltage is
CC
disables the low-voltage detection.
CC
is pulled LOW and the battery voltage is
ENB
, connected
CS
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Ordering Information
Voltage Grade Accuracy Order Information Supplied As
4.1V A
4.1V A
4.1V Standard
4.1V Standard
4.2V A
4.2V A
4.2V Standard
4.2V Standard
8.2V A
8.2V A
8.2V Standard
8.2V Standard
8.4V A
8.4V A
8.4V Standard
8.4V Standard
±
30mV LM3622AM-4.1 95 unit increments in rail
±
30mV LM3622AMX-4.1 2500 unit increments in tape and reel
±
50mV LM3622M-4.1 95 unit increments in rail
±
50mV LM3622MX-4.1 2500 unit increments in tape and reel
±
30mV LM3622AM-4.2 95 unit increments in rail
±
30mV LM3622AMX-4.2 2500 unit increments in tape and reel
±
50mV LM3622M-4.2 95 unit increments in rail
±
50mV LM3622MX-4.2 2500 unit increments in tape and reel
±
60mV LM3622AM-8.2 95 unit increments in rail
±
60mV LM3622AMX-8.2 2500 unit increments in tape and reel
±
100mV LM3622M-8.2 95 unit increments in rail
±
100mV LM3622MX-8.2 2500 unit increments in tape and reel
±
60mV LM3622AM-8.4 95 unit increments in rail
±
60mV LM3622AMX-8.4 2500 unit increments in tape and reel
±
100mV LM3622M-8.4 95 unit increments in rail
±
100mV LM3622MX-8.4 2500 unit increments in tape and reel
LM3622
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