LTC4069-4.4 Linear Technology, LTC4069-4.4 Datasheet - Page 7

• Manufacturer Part Number: LTC4069-4.4
• Description: Standalone 750mA Li-Ion Battery Charger in 2 x 2 DFN
• Manufacturer: Linear Technology

SIMPLIFIED BLOCK DIAGRAM
OPERATION
The LTC4069-4.4 is a linear battery charger designed
primarily for charging single-cell lithium-ion batteries.
Featuring an internal P-channel power MOSFET, the
charger uses a constant-current/constant-voltage charge
algorithm with programmable current. Charge current can
be programmed up to 750mA with a fi nal fl oat voltage
accuracy of ±0.6%. The CHRG open-drain status output
indicates if C/10 has been reached. No blocking diode
or external sense resistor is required; thus, the basic
charger circuit requires only two external components.
An internal termination timer and trickle charge low-
battery conditioning adhere to battery manufacturer safety
guidelines.
V
CC
R
NOM
R
NTC
5
2
NTC
CHRG
V
CC
R7
R8
R9
R10
–
+
+
–
+
–
PROG
C1
C2
C3
+
C/10
0.1V
–
COLD
TOO
HOT
TOO
NTC_EN
2.9V
BAT
OR
115°C
T
DIE
REF
–
+
LOBAT
AND
R3
R4
R5
Figure 1. LTC4069-4.4 Block Diagram
+
–
TA
1V
0.1V
1.2V
SUSPEND
D3
–
CA
D1
+
Furthermore, the LTC4069-4.4 is capable of operating
from a USB power source.
An internal thermal limit reduces the programmed charge
current if the die temperature attempts to rise above a
preset value of approximately 115°C. This feature protects
the LTC4069-4.4 from excessive temperature and allows
the user to push the limits of the power handling capability
of a given circuit board without risk of damaging the
LTC4069-4.4 or external components. Another benefi t
of the LTC4069-4.4 thermal limit is that charge current
can be set according to typical, not worst-case, ambient
M2
1
MP
6
PROG
R
PROG
4V
–
+
–
ENABLE
V
MA
4
CC
C4
V
CC
+
1
M1
1000
GND
R1
R2
SUSPEND
+
SHUTDOWN
VA
CHARGE CONTROL
D2
–
3.6V
LOGIC
1.2V
www.DataSheet4U.com
+
–
LTC4069-4.4
C5
OSCILLATOR
COUNTER
UVLO
BAT
4069 F01
3
+
406944fa
7