LTC1732EMS-8.4 Linear Technology, LTC1732EMS-8.4 Datasheet - Page 5

• Manufacturer Part Number: LTC1732EMS-8.4
• Description: IC BATTCHRG CNTRLR LI-ION 10MSOP
• Manufacturer: Linear Technology

Specifications of LTC1732EMS-8.4

• Function: Charge Management
• Battery Type: Li-Ion, NiCd, NiMH
• Voltage - Supply: 4.5 V ~ 12 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: LTC1732EMS8.4

PIN
BAT (Pin 1): Battery Sense Input. A bypass capacitor of
10 F or more is required to keep the loop stable when the
battery is not connected. A precision internal resistor
divider sets the final float voltage. The resistor divider is
disconnected in sleep mode to reduce the current drain on
the battery.
SEL (Pin 2): This pin must be connected to V
CHRG (Pin 3): Open-Drain Charge Status Output. When
the battery is charging, the CHRG pin is pulled low by an
internal N-channel MOSFET. When the charge current
drops to 10% of the full-scale current for more than 15ms,
the N-channel MOSFET turns off and a 35 A current
source is connected from the CHRG pin to GND. When the
timer runs out or the input supply is removed, the current
source is disconnected and the CHRG pin is forced into a
high impedance state.
TIMER (Pin 4): Timer Capacitor and Constant-Voltage
Mode Disable Input Pin. The timer period is set by placing
a capacitor, C
(C
connected to V
voltage mode is turned off and the IC will operate in
constant-current mode only. Shorting the TIMER pin to
GND will disable the internal timer function and the C/10
function.
GND (Pin 5): Ground.
TIMER
U
FUNCTIONS
• 3 hours)/(0.1 F). When the TIMER pin is
U
TIMER
CC
, the timer is disabled, thus the constant-
, to GND. The timer period is t
U
CC
.
TIMER
=
PROG (Pin 6): Charge Current Program and Shutdown
Input Pin. The charge current is programmed by connect-
ing a resistor, R
= (V
into shutdown by floating the PROG pin and allowing the
internal 2.5 A current source to pull the pin above the
2.457V shutdown threshold voltage.
DRV (Pin 7): Drive Output Pin for the P-Channel MOSFET
or PNP Transistor. If a PNP transistor is used, it must have
high gain (see Applications Information section).
V
8.8V to 12V. If V
when the input supply is disconnected, then the IC enters
sleep mode with I
capacitor.
SENSE (Pin 9): Current Sense Input. A sense resistor,
R
This resistor is chosen using the following equation:
ACPR (Pin 10): Wall Adapter Present Output. When the
input voltage (wall adapter) is applied to the LTC1732-8.4,
this pin is pulled to ground by an internal N-channel
MOSFET which is capable of sinking 5mA to drive an
external LED (See Applications Information Section).
CC
SENSE
R
PROG
SENSE
(Pin 8): Input Supply Voltage. V
, must be connected from V
• 800 )/(R
= (V
PROG
PROG
CC
drops below V
CC
• 800 )/(R
PROG
to ground. The charge current is I
< 30 A. Bypass this pin with a 1 F
• R
SENSE
PROG
BAT
LTC1732-8.4
). The IC can be forced
CC
+ 54mV, for example
• I
CC
to the SENSE pin.
BAT
can range from
)
17328f
5
BAT