LTC4053EMSE-4.2 Linear Technology, LTC4053EMSE-4.2 Datasheet - Page 6

• Manufacturer Part Number: LTC4053EMSE-4.2
• Description: IC CHARGER BATTERY USB 10-MSOP
• Manufacturer: Linear Technology

Specifications of LTC4053EMSE-4.2

• Function: Charge Management
• Battery Type: Lithium-Ion (Li-Ion)
• Voltage - Supply: 4.25 V ~ 6.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width) Exposed Pad
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

PI FU CTIO S
LTC4053-4.2
CHRG: Open-Drain Charge Status Output. When the
battery is being charged, the CHRG pin is pulled low by an
internal N-channel MOSFET. When the charge current
drops to 10% of the full-scale current, the N-channel
MOSFET latches off and a 30µA current source is con-
nected from the CHRG pin to ground. The C/10 latch can
be cleared by grounding the SHDN pin, momentarily, or
toggling V
is removed, the current source is disconnected and the
CHRG pin is forced high impedance.
V
35mV of V
threshold, the LTC4053 enters sleep mode, dropping I
to less than 3µA. V
Bypass this pin with at least a 4.7µF ceramic capacitor to
ground.
FAULT: Open-Drain Fault Status Output. The FAULT open-
drain logic signal indicates that the charger has timed out
under trickle charge conditions or the NTC comparator is
indicating an out-of-range battery temperature condition.
If V
the charge current drops to one tenth of its programmed
value and the timer period is reduced by a factor of four.
When one fourth of the timing period has elapsed, if V
is still less than 2.48V, trickle charging stops and the
FAULT pin latches to ground. The fault can be cleared by
toggling V
pulling the BAT pin above 2.48V. If the NTC comparator is
indicating an out-of-range battery temperature condition,
the FAULT pin will pull to ground until the temperature
returns to the acceptable range.
TIMER: Timer Capacitor. The timer period is set by placing
a capacitor, C
Short the TIMER pin to ground to disable the internal timer
function.
GND: Ground. The exposed backside of the package is also
ground and must be soldered to the PC board for maxi-
mum heat transfer.
6
CC
Time (Hours) = (C
U
BAT
: Positive Input Supply Voltage. When V
is less that 2.48V, trickle charging begins whereby
U
CC
CC
BAT
. When the timer runs out or the input supply
, momentarily grounding the SHDN pin or
TIMER
or less than the undervoltage lockout
, to ground. The timer period is:
U
CC
TIMER
can range from 4.25V to 6.5V.
• 3 hr)/(0.1µF)
CC
is within
BAT
BAT
NTC: Input to the NTC (Negative Temperature Coefficient)
Thermistor Temperature Monitoring Circuit. With an ex-
ternal 10kΩ NTC thermistor to ground and a 1% resistor
to V
pack and stop charging when it is out of range. When the
voltage at this pin drops below (0.5)•(V
tures or rises above (0.875)•(V
suspended and the internal timer is frozen. The CHRG pin
output status is not affected in this hold state. The FAULT
pin will be pulled to ground, but not latched. When the
temperature returns to an acceptable range, charging will
resume and the FAULT pin will be released. The NTC
feature can be disabled by grounding the NTC pin.
PROG: Charge Current Program and Charge Current Moni-
tor Pin. The charge current is programmed by connecting
a resistor, R
mode, the LTC4053 servos the PROG pin voltage to 1.5V.
In all modes the voltage on the PROG pin can be used to
measure the charge current as follows:
SHDN: Shutdown Input Pin. Pulling the SHDN pin to
ground will put the LTC4053 into standby mode where the
BAT drain current is reduced to less than 3µA, and the
supply current is reduced to less than 25µA. For normal
operation, pull the SHDN pin up to V
BAT: Charge Current Output. A bypass capacitor of at least
1µF with a 1Ω series resistor is required to keep the loop
stable when the battery is not present. A precision internal
resistor divider sets the final float potential on this pin. The
internal resistor divider is disconnected in sleep and
shutdown mode.
ACPR: Open-Drain Power Supply Status Output. When
V
and at least 35mV above V
ground. Otherwise, the pin is high impedance.
CC
I
BAT
CC
is greater than the undervoltage lockout threshold
, this pin can sense the temperature of the battery
= (V
PROG
PROG
/R
to ground. When in constant-current
PROG
) • 1000.
BAT
, the ACPR pin will pull to
CC
) at cold, charging is
CC
CC
.
) at hot tempera-
4053fa