pt6112 China Resources Powtech (Shanghai) Co., Ltd, pt6112 Datasheet - Page 5

• Manufacturer Part Number: pt6112
• Description: Standalone Linear Li-ion Battery Charger With Thermal Regulation
• Manufacturer: China Resources Powtech (Shanghai) Co., Ltd

SIMPLIFIED BLOCK DIAGRAM
OPERATION DESCRIPTION
The PT6112 is a standalone linear Li-ion battery
charger with thermal regulation. With the internal 0.6
ohms MOSFET, the minimum operating voltage can be
less than 4.25V. One external 1% precision resistor is
required to set the charging current value. When the
voltage at the VCC pin rises above the UVLO threshold,
the normal charging cycle begins.
voltage is less than 2.9V, the device will operate in a
trickle charging mode. The charging current in the
trickle charging mode is 1/10
value, which effectively protects the battery from
damage and prolongs its lifetime. When the voltage at
the BAT pin rises above 2.9V, the charger enters the
constant-current mode in which case the charging
China Resources Powtech (Shanghai) Limited
PT6112_DS Rev EN_1.0
1
CHG
120
T
DIE
o
C
th
T
SHDN
A
of the programmed
STANDBY
If the battery
C3
C2
WWW.CRPOWTECH.COM
2.9V
BAT
Charger with Thermal Regulation
1X
Standalone Linear Li-Ion Battery
current equals to the programmed value. Once the
voltage at the BAT pin reaches 4.2V, the charger goes
into the constant voltage mode where the charging
current decreases. Once the charging current drops to
1/10
After a charge cycle is complete and the charging
operation is terminated, the PT6112 keeps monitoring
the BAT voltage. It will recharge the battery as soon as
the BAT voltage drops below 4.05V. The PT6112
includes a soft-start circuit to minimize the inrush
current at the start of a charge cycle. When the PROG
pin is floating, the charger goes into the shutdown
mode. It acts as chip enable pin.
5
PROG
3uA
th
the programmed value, the charging cycle ends.
M
A
4
V
0.1V
1V
V
CC
R5
R3
R4
CC
A
V
1.5uA
VREF
1.21V
GND
2
1000X
R1
R2
BAT
PT6112
3
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