Datasheet

LT3740
4
3740fc
TYPICAL PERFORMANCE CHARACTERISTICS
Shutdown vs Maximum V
C
V
C
vs Current Sensing Threshold
Feedback Reference Voltage
vs Temperature
PGOOD Threshold vs Temperature
Shutdown Threshold
vs Temperature
Switching Frequency
vs Temperature
SHUTDOWN (V)
0
MAXIMUM V
C
(V)
1.0
0.8
1.6
1.4
1.8
1.2
2.0
3740 G07
0.6
0.4
0.2
0
1.5 210.5
2.5
3
V
C
(V)
1
CURRENT SENSING THRESHOLD (mV)
150
250
200
300
3740 G08
100
50
0
1.4 1.61.51.31.1 1.2
1.7
1.8
RANGE = V
IN
RANGE =
OPEN
RANGE = GND
TEMPERATURE (°C)
–50
V
FB
(mV)
800
806
808
804
802
810
3740 G09a
798
796
792
794
790
25 75500–25
100
TEMPERATURE (°C)
–50
V
FB
(mV)
740
760
750
770
3740 G09b
730
720
710
25 500–25
75
100
TEMPERATURE (°C)
–50
0.8
1.1
1.0
0.9
1.2
3740 G10
0.7
0.6
0.5
0.4
25 500–25
75
100
SHDN (V)
TEMPERATURE (°C)
–50
CONTROLLER FREQUENCY (KHz)
300
315
310
305
320
3740 G11
295
290
285
280
25 500–25
75
100
(T
A
= 25°C, unless otherwise noted)
XREF Pin Start-Up
Load Regulation
Current Limit vs Bottom Gate
On-Time
SS
0.5V/DIV
V
O
2V/DIV
I
L
2A/DIV
3740 G04
V
IN
= 10V, V
OUT
= 2.5V
I
LOAD
= 3A
2ms/DIV
LOAD CURRENT (A)
0
DV
OUT
(%)
–0.3
–0.4
–0.1
–0.2
0
8
3740 G05
–0.5
–0.6
–0.7
–0.8
2
4
6
10
RANGE = V
IN
RANGE = OPEN
RANGE = GND
V
IN
= 10V
V
OUT
= 2.5V
R
S
= 12mΩ
BOTTOM GATE ON DUTY CYCLE (%)
30
CURRENT SENSING LIMIT (mV)
100
80
160
140
180
120
200
90
3740 G06
60
40
20
0
50 6040
70
80
100
RANGE = V
IN
RANGE = OPEN
RANGE = GND