Datasheet

LTC3731
7
3731fc
TYPICAL PERFORMANCE CHARACTERISTICS
Maximum I
SENSE
vs V
RUN/SS
Maximum Current Sense
Threshold vs Duty Factor Peak Current Threshold vs V
ITH
Percentage of Nominal Output
vs Peak I
SENSE
(Foldback)
Maximum Duty Factor
vs Temperature I
SENSE
Pin Current vs V
OUT
Short-Circuit Arming and Latchoff
vs Temperature Supply Current vs Temperature
RUN/SS Pull-Up Current
vs Temperature
–50 0 25 50 75–25 125100
0
RUN/SS PIN VOLTAGE (V)
1
3
4
5
2
TEMPERATURE (°C)
3731 G10
ARMING
LATCHOFF
–50 0 25 50 75–25 125100
0
SUPPLY CURRENT (mA)
SHUTDOWN CURRENT (µA)
0.4
2.0
1.6
2.4
2.8
1.2
0.8
TEMPERATURE (°C)
3731 G11
100
80
60
40
20
0
V
CC
= 5V
–50 0 25 50 75–25 125100
0
RUN/SS PULL-UP CURRENT (µA)
0.5
1.5
2.0
2.5
1.0
TEMPERATURE (°C)
3731 G12
V
RUN/SS
= 1.9V
V
RUN/SS
VOLTAGE (V)
0
MAXIMUM I
SENSE
(mV)
80
70
60
50
40
30
20
10
0
4
3731 G13
1
2
3
5 6
DUTY FACTOR (%)
0
0
I
SENSE
VOLTAGE (mV)
25
50
75
20 40 60 80
3731 G14
100
V
ITH
(V)
0
I
SENSE
VOLTAGE THRESHOLD (mV)
75
60
45
30
15
0
–15
0.6 1.2 1.8 2.4
3731 G15
PERCENTAGE OF NOMINAL OUTPUT VOLTAGE (%)
0
PEAK I
SENSE
VOLTAGE (mV)
80
70
60
50
40
30
20
10
0
80
3731 G16
2010 30 50 70 90
40
60
100
–50 0 25 50 75–25 125100
90
MAXIMUM DUTY FACTOR (%)
92
96
98
100
94
TEMPERATURE (°C)
3731 G17
V
PLLFLTR
= 0V
V
OUT
(V)
0
I
SENSE
PIN CURRENT (µA)
40
30
20
10
0
–10
–20
–30
3731 G18
2
5
1
3 4