Datasheet
LTC3677-3
15
36773f
INPUT VOLTAGE (V)
0
0
OVGATE (V)
2
4
6
8
10
12
2 4 6 8
36773 G36
OVSENS CONNECTED
TO INPUT THROUGH
6.2k RESISTOR
I
OUT
(mA)
0
600
500
400
300
200
100
0
–100
300 500
36773 G40
100 200
400 600
CURRENT (mA)
I
LOAD
I
IN
I
BAT
(CHARGING)
I
BAT
(DISCHARGING)
WALL = 0V
R
PROG
= 2k
R
CLPROG
= 2k
LDO1
50mV/DIV
(AC)
LDO2
20mV/DIV
(AC)
I
OUT1
100mA
5mA
36773 G37
20µs/DIVLDO1 = 1.2V
LDO2 = 2.5V
I
LDO2
= 40mA
V
OUT
= V
BAT
= 3.8V
V
BAT
(V)
3.8
0
I
BAT
(mA)
20
60
80
100
200
140
3.9
4.0
36773 G38
40
160
180
120
4.1
4.2
V
NTC
< V
TOO_HOT
V
BUS
= 0V
OVGATE vs OVSENS
Typical perForMance characTerisTics
Too Hot BAT Discharge
T
J
= 25°C unless otherwise specified
LDO Load Step
Input and Battery Current
vs Output Current
Battery Discharge vs Temperature
TEMPERATURE (°C)
50
BATTERY DISCHARGE CURRENT (mA)
175
80
36773 G39
100
50
60 70 90
25
0
200
150
125
75
100 110 120
V
BUS
= 5V
V
BUS
= 0V
V
BAT
= 4.1V
V
NTC
< V
TOO_HOT
5x MODE
I
VOUT
= 0mA
I
LIM0
, I
LIM1
(Pins 1, 2): Input Current Control Pins. I
LIM0
and I
LIM1
control the input current limit. See Table 1 in the
USB PowerPath Controller section. Both pins are pulled
low by a weak current sink.
NC (Pins 3, 9, 18, 19, 20, 22): No Connect. This pin has
no function and may be floated or connected to ground.
WALL (Pin 4): Wall Adapter Present Input. Pulling this
pin above 4.3V will disconnect the power path from V
BUS
to V
OUT
. The ACPR pin will also be pulled low to indicate
that a wall adapter has been detected.
SW3 (Pin 5): Power Transmission (Switch) Pin for Step-
Down Switching Regulator 3 (Buck3).
V
IN3
(Pin 6): Power Input for Step-Down Switching Regu-
lator 3. This pin should be connected to V
OUT
.
FB3 (Pin 7): Feedback Input for Step-Down Switching
Regulator 3 (Buck3). This pin servos to a fixed voltage of
0.8V when the control loop is complete.
OVSENSE (Pin 8): Overvoltage Protection Sense Input.
OVSENSE should be connected through a 6.2k resistor
to the input power connector and the drain of an external
pin FuncTions