Datasheet

LTC3728L/LTC3728LX
6
3728lxff
Typical perForMance characTerisTics
Efficiency vs Output Current
and Mode (Figure 13)
Efficiency vs Output Current
(Figure 13)
Efficiency vs Input Voltage
(Figure 13)
Supply Current vs Input Voltage
and Mode (Figure 13) EXTV
CC
Voltage Drop
INTV
CC
and EXTV
CC
Switch
Voltage vs Temperature
Internal 5V LDO Line Regulation
Maximum Current Sense
Threshold vs Duty Factor
Maximum Current Sense
Threshold vs Percent of Nominal
Output Voltage (Foldback)
OUTPUT CURRENT (A)
0.001
0
EFFICIENCY (%)
10
30
40
50
100
70
0.01
0.1
1
3728L G01
20
80
90
60
10
FORCED
CONTINUOUS
MODE (PWM)
CONSTANT
FREQUENCY
(BURST DISABLE)
Burst Mode
OPERATION
V
IN
= 15V
V
OUT
= 5V
f = 250kHz
OUTPUT CURRENT (A)
0.001
EFFICIENCY (%)
70
80
10
3728L G02
60
50
0.01
0.1
1
100
90
V
IN
= 10V
V
IN
= 15V
V
IN
= 7V
V
IN
= 20V
V
OUT
= 5V
f = 250kHz
INPUT VOLTAGE (V)
5
EFFICIENCY (%)
70
80
3728L G03
60
50
15
25
35
100
V
OUT
= 5V
I
OUT
= 3A
f = 250kHz
90
INPUT VOLTAGE (V)
0 5
0
SUPPLY CURRENT (µA)
400
1000
10
20
25
3728L G04
200
800
600
15
30
SHUTDOWN
BOTH
CONTROLLERS ON
CURRENT (mA)
0
EXTV
CC
VOLTAGE DROP (mV)
150
200
40
3728L G05
100
50
0
10
20
30
TEMPERATURE (°C)
–50
INTV
CC
AND EXTV
CC
SWITCH VOLTAGE (V)
4.95
5.00
5.05
25 75
3728L G06
4.90
4.85
–25 0
50 100 125
4.80
4.70
4.75
INTV
CC
VOLTAGE
EXTV
CC
SWITCHOVER THRESHOLD
INPUT VOLTAGE (V)
0
4.8
4.9
5.1
15 25
3728L G07
4.7
4.6
5 10
20 30
4.5
4.4
5.0
INTV
CC
VOLTAGE (V)
I
LOAD
= 1mA
DUTY FACTOR (%)
0
0
V
SENSE
(mV)
25
50
75
20 40 60 80
3728L G08
100
PERCENT ON NOMINAL OUTPUT VOLTAGE (%)
0
V
SENSE
(mV)
40
50
60
100
3728L G09
30
20
0
25
50
75
10
80
70