LTC4063 LINER [Linear Technology], LTC4063 Datasheet - Page 12

• Manufacturer Part Number: LTC4063
• Description: Standalone Linear Li-Ion Charger with Micropower Low Dropout Linear Regulator
• Manufacturer: LINER [Linear Technology]

APPLICATIO S I FOR ATIO
LTC4063
When the charge current (I
the CHRG output is in its pull-down state. When the
charger enters constant-voltage mode operation and the
charge current falls below I
becomes high impedance, indicating that the battery is
12
Figure 2. Charge Time Termination. The Charger
Automatically Shuts Off After 3 Hours
R
V
PROG
IN
2k
R
DET
1k
U
POWER ON
V
CHRG
PROG
IDET
CC
U
LTC4063
Figure 3. State Diagram of a Charge Cycle Using Charge Time Termination
GND
BAT
TIMER
DETECT
BAT
) is greater than I
W
2.9V < BAT < 4.1V
BAT > 4.1V
TIME ELAPSES
, the CHRG output
1/2 CHARGE
BAT < 2.9V
C
0.1µF
500mA
TIMER
4063 F02
+
U
CHRG STATE: SQUARE WAVE
CHRG STATE: PULL-DOWN
CHRG STATE:
PULL-DOWN IF I
Hi-Z IF I
CHRG STATE: Hi-Z
CHRG STATE:
PULL-DOWN IF I
Hi-Z IF I
TRICKLE CHARGE MODE
DETECT
NO CHARGE CURRENT
NO CHARGE CURRENT
1/10 FULL CURRENT
RECHARGE MODE
STANDBY MODE
CHARGE MODE
FULL CURRENT
FULL CURRENT
BAT
BAT
FAULT MODE
< I
< I
,
DETECT
DETECT
BAT
BAT
1/4 CHARGE TIME
ELAPSES
BAT > 2.9V
CHARGE TIME
ELAPSES
BAT < 4.1V
> I
> I
almost fully charged. The CHRG output will also become
high impedance once the charge time elapses. If the IDET
pin is not connected, the CHRG output remains in its pull-
down state until the charge time elapses and terminates
the charge cycle.
Figure 2 shows a charger circuit using charge time termi-
nation that is programmed to charge at 500mA. Once the
charge current drops below 100mA in constant-voltage
mode (as set by R
This indicates to the user that the battery is almost fully
charged and ready to use. The LTC4063 continues to
charge the battery until the internal timer reaches 3 hours
(as set by C
charges the battery until the internal timer reaches 1.5
hours. Figure 3 describes the operation of the LTC4063
charger when Charge Time Termination is used.
DETECT
DETECT
4063 F03
TIMER
UVLO CONDITION
CHGEN = 5V
CHRG STATE: Hi-Z
). During recharge cycles, the LTC4063
DET
OR
I
SHUTDOWN MODE
CC
), the CHRG output turns off the LED.
DROPS TO 35µA
CHGEN = 0V
OR UVLO
CONDITION
STOPS
4063fb