Datasheet

5
LT1506
TYPICAL PERFORMANCE CHARACTERISTICS
UW
Frequency Foldback
FEEDBACK PIN VOLTAGE (V)
0
SWITCHING FREQUENCY (kHz) OR CURRENT (µA)
500
400
300
200
100
0
2.0
1506 G10
0.5
1.0
1.5
2.5
SWITCHING
FREQUENCY
FEEDBACK PIN
CURRENT
Inductor Core Loss for 3.3V Output
INDUCTANCE (µH)
02
CORE LOSS (W)
1.0
0.1
0.01
0.001
46810
1506 G01
TYPE 52
Metglas
®
Kool Mµ
®
PERMALLOY
µ = 125
Switching Frequency
TEMPERATURE (°C)
–50
550
540
530
520
510
500
490
480
470
460
450
100
1506 G11
–25 0 25 50 75 125
FREQUENCY (kHz)
BOOST Pin Current
SWITCH CURRENT (A)
0
0
BOOST PIN CURRENT (mA)
10
20
40
30
60
50
12
3
45
1506 G14
80
70
100
90
DUTY CYCLE = 100%
Maximum Load Current
at V
OUT
= 3.3V
INPUT VOLTAGE (V)
4
4.0
4.2
4.4
12
1506 G13
3.8
3.6
610814
3.4
3.2
3.0
LOAD CURRENT (A)
L= 10µH
L= 5µH
L= 3µH
L= 1.8µH
Maximum Load Current
at V
OUT
= 5V
INPUT VOLTAGE (V)
5
2.6
LOAD CURRENT (A)
2.8
3.2
3.4
3.6
9
13
15
4.4
1506 G17
3.0
711
3.8
4.0
4.2
L= 10µH
L= 5µH
L= 3µH
L= 1.8µH
Switch Voltage Drop
SWITCH CURRENT (A)
0
SWITCH VOLTAGE (mV)
250
200
400
125°C
25°C
350
300
45
1506 G16
150
100
50
0
1
2
3
500
450
–40°C
V
C
Pin Shutdown Threshold
JUNCTION TEMPERATURE (°C)
–50
1.4
1.2
1.0
0.8
0.6
0.4
100
1506 G15
–25 0 25 50 75 125
THRESHOLD VOLTAGE (V)
SHUTDOWN
OUTPUT VOLTAGE (%)
0
5
6
7
80
1506 G18
4
3
20 40 60 100
2
1
0
OUTPUT CURRENT (A)
FOLDBACK
CHARACTERISTICS
CURRENT
SOURCE
LOAD
RESISTOR
LOAD
MOS LOAD
POSSIBLE UNDESIRED
STABLE POINT FOR
CURRENT SOURCE
LOAD*
Current Limit Foldback
Kool Mµ is a registered trademark of Magnetics, Inc.
Metglas is a registered trademark of AlliedSignal Inc.
*See “More Than Just Voltage Feedback” in the Applications Information section.