Datasheet

LT3684
4
3684f
Effi ciency (V
OUT
= 5.0V)
Effi ciency (V
OUT
= 3.3V)
Maximum Load Current
Switch Voltage Drop
Boost Pin Current
Switch Current Limit
Maximum Load Current
Switch Current Limit
Effi ciency
LOAD CURRENT (A)
0
EFFICIENCY (%)
80
90
100
1.6
3684 G01
70
60
50
0.2 0.4 0.6
0.8 1.0
1.2 1.4 1.8
2.0
V
IN
= 12V
V
IN
= 24V
L: NEC PLC-0745-4R7
f = 800kHz
LOAD CURRENT (A)
0
EFFICIENCY (%)
70
75
80
85
90
1.6
3684 G02
65
60
55
50
0.2 0.4 0.6
0.8 1.0
1.2 1.4 1.8
2.0
V
IN
= 12V
V
IN
= 7V
V
IN
= 24V
L: NEC PLC-0745-4R7
f = 800kHz
SWITCHING FREQUENCY (MHz)
0
EFFICIENCY (%)
85
1.5
3684 G03
70
60
0.5 1 2
55
50
90
80
75
65
2.5 3
V
IN
= 12V
V
IN
= 24V
V
OUT
= 3.3V
L = 10µH
LOAD = 1A
INPUT VOLTAGE (V)
5
LOAD CURRENT (A)
15
3684 G04
2.5
10 20
1.5
1.0
4.0
3.5
3.0
2.0
25 30
TYPICAL
MINIMUM
V
OUT
= 3.3V
T
A
= 25°C
L = 4.7µH
f = 800kHz
INPUT VOLTAGE (V)
5
LOAD CURRENT (A)
15
3684 G05
2.5
10 20
1.5
1.0
4.0
3.5
3.0
2.0
25 30
TYPICAL
MINIMUM
V
OUT
= 5V
T
A
= 25°C
L = 4.7µH
f = 800kHz
DUTY CYCLE (%)
0
SWITCH CURRENT LIMIT (A)
40
3684 G06
2.5
20 60
1.5
1.0
4.0
3.5
3.0
2.0
80 100
TEMPERATURE (°C)
–50
SWITCH CURRENT LIMIT (A)
2.0
2.5
3.0
125
3684 G07
1.5
1.0
0
0–25 5025 10075
0.5
4.5
4.0
DUTY CYCLE = 10 %
DUTY CYCLE = 90 %
SWITCH CURRENT (mA)
0
400
500
700
1500 2500
3684 G08
300
200
500 1000
2000 3000 3500
100
0
600
VOLTAGE DROP (mV)
SWITCH CURRENT (mA)
0
0
BOOST PIN CURRENT (mA)
10
30
40
50
2000
90
3684 G09
20
1000
500
2500 3000
1500 3500
60
70
80
(T
A
= 25°C unless otherwise noted)
TYPICAL PERFORMANCE CHARACTERISTICS