LT3684
TYPICAL PERFORMANCE CHARACTERISTICS
Feedback Voltage
1.290
1.285
FEEDBACK VOLTAGE (V)
1.280
FREQUENCY (MHz)
1.275
1.270
1.265
1.260
1.255
1.250
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
1.20
1.15
1.10
1.05
1.00
0.95
0.90
0.85
0.80
–50
–25
0
25
50
75
TEMPERATURE (°C)
100
125
SWITCHING FREQUENCY (kHz)
(T
A
= 25°C unless otherwise noted)
Frequency Foldback
1200
R
T
= 45.3k
1000
800
600
400
200
0
0
200
400 600 800 1000 1200 1400
FB PIN VOLTAGE (mV)
3684 G12
Switching Frequency
R
T
= 45.3k
3684 G10
3684 G11
Minimum Switch On-Time
140
MINIMUM SWITCH ON-TIME (ns)
120
SWITCH CURRENT LIMIT (A)
100
80
60
40
20
0
–50
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
–25
25
0
50
75
TEMPERATURE (˚C)
100
125
Soft-Start
12
10
8
6
4
2
0
0
0.5
2
2.5
1.5
RUN/SS PIN VOLTAGE (V)
1
3
3.5
3684 G14
RUN/SS Pin Current
RUN/SS PIN CURRENT (µA)
0
5
20
30
15
25
10
RUN/SS PIN VOLTAGE (V)
35
3684 G15
3684 G13
Boost Diode
1.6
1.4
V
C
PIN CURRENT (µA)
BOOST DIODE V
f
(V)
1.2
1.0
0.8
0.6
0.4
0.2
0
0
1.0
0.5
1.5
BOOST DIODE CURRENT (A)
2.0
3684 G16
Error Amp Output Current
100
80
60
40
20
0
–20
–40
–60
–80
1.065
1 .265
1.165
1.365
FB PIN VOLTAGE (V)
1.465
3684 G17
Minimum Input Voltage
4.5
4.0
INPUT VOLTAGE (V)
3.5
3.0
V
OUT
= 3.3V
T
A
= 25°C
L = 4.7µH
f = 800kHz
0.1
0.01
1
LOAD CURRENT (A)
10
3684 G18
2.5
2.0
0.001
3684f
5
LINER [ LINEAR TECHNOLOGY ]
