Datasheet

8
LTC4011
4011fa
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PI FU CTIO S
DCIN (Pin 1): DC Power Sense Input. The LTC4011 senses
voltage on this pin to determine when an external DC
power source is present. This input should be isolated
from V
CC
by a blocking diode or PowerPath FET. Refer to
the Applications Information section for complete details.
Operating voltage range is GND to 34V.
FAULT (Pin 2): Active-Low Fault Indicator Output. The
LTC4011 indicates various battery and internal fault con-
ditions by connecting this pin to GND. Refer to the Opera-
tion and Applications Information sections for further
details. This output is capable of driving an LED and should
be left floating if not used. FAULT is an open-drain output
to GND with an operating voltage range of GND to V
CC
.
CHRG (Pin 3): Active-Low Charge Indicator Output. The
LTC4011 indicates it is providing charge to the battery by
connecting this pin to GND. Refer to the Operation and
Applications Information sections for further details. This
output is capable of driving an LED and should be left
floating if not used. CHRG is an open-drain output to GND
with an operating voltage range of GND to V
CC
.
CHEM (Pin 4): Battery Chemistry Selection Input. This pin
should be wired to GND to select NiMH fast charge
termination parameters. If a voltage greater than 2.85V is
applied to this pin, or it is left floating, NiCd parameters are
used. Refer to the Applications Information section for
further details. Operating voltage range is GND to 3.3V.
GND (Pin 5): Ground. This pin provides a single-point
ground for internal references and other critical analog
circuits.
V
RT
(Pin 6): Thermistor Network Termination Output. The
LTC4011 provides 3.3V on this pin to drive an external
thermistor network connected between V
RT,
V
TEMP
and
GND. Additional power should not be drawn from this pin
by the host application.
V
TEMP
(Pin 7): Battery Temperature Input. An external
thermistor network may be connected to V
TEMP
to pro-
vide temperature-based charge qualification and addi-
tional fast charge termination control. Charging may also
be paused by connecting the V
TEMP
pin to GND. Refer to
the Operation and Applications Information sections for
complete details on external thermistor networks and
charge control. If this pin is not used it should be wired
to V
RT
. Operating voltage range is GND to 3.3V.
V
CELL
(Pin 8): Average Single-Cell Voltage Input. An
external voltage divider between BAT and V
CDIV
is attached
to this pin to monitor the average single-cell voltage of the
battery pack. The LTC4011 uses this information to pro-
tect against catastrophic battery overvoltage and to con-
trol the charging state. Refer to the Applications Information
section for further details on the external divider network.
Operating voltage range is GND to BAT.
TYPICAL PERFOR A CE CHARACTERISTICS
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INTV
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Voltage INTV
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Short-Circuit Current