LT3653
TYPICAL PERFORMANCE CHARACTERISTICS
V
C
Current
15
10
VC PIN CURRENT (μA)
5
0
–5
–10
–15
–20
–25
4
4.4
4.8
5.2
V
OUT
(V)
5.6
6
3653 G09
T
A
= 25°C unless otherwise noted
V
C
Operating Range
2.0
1.8
1.6
VC VOLTAGE (V)
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0.0
-50
-25
0
25
50
75
TEMPERATURE (ºC)
100
125
SWITCHING THRESHOLD
CURRENT LIMIT CLAMP
3653 G10
PIN FUNCTIONS
V
IN
(Pin 1):
The V
IN
pin supplies current to the LT3653’s
internal regulator and the internal power switch. Locally
bypass this pin with a capacitor.
HVOK (Pin 2):
The HVOK pin is a status pin which indi-
cates that the internal bias rail is present and that an input
undervoltage lockout fault, an overvoltage lockout fault or
an over temperature fault are not present.
V
C
(Pin 3):
The V
C
pin is the output of the internal error
amplifier and is internally compensated. The voltage on this
pin controls the peak switch current. Connect this pin to
the battery charger V
C
pin for battery tracking function.
I
LIM
(Pin 4):
Connect a resistor to GND to program the
output current limit of the regulator. See the I
LIM
Resistor
section in Application Information.
V
OUT
(Pin 5):
The V
OUT
pin is connected to the negative
terminal of the internal current sense resistor of the output
current limit circuit. Maximum V
OUT
voltage is regulated
to 4.8V.
I
SENSE
(Pin 6):
The I
SENSE
pin is the positive input to the
internal current sense resistor of the output current limit
circuit. The I
SENSE
pin is also the anode of the internal
BOOST diode.
BOOST (Pin 7):
The BOOST pin provides a drive voltage,
higher than the input voltage, to the internal power switch.
The BOOST pin is internally connected to the cathode of
the BOOST diode.
SW (Pin 8):
The SW pin is the output of the internal power
switch. Connect this pin to the inductor, catch diode and
boost capacitor.
Exposed Pad (Pin 9):
Ground. The Exposed Pad must be
soldered to the PCB and electrically connected to ground.
Use a large ground plane and vias to optimize thermal
performance.
3653f
5
LINER [ LINEAR TECHNOLOGY ]
