LT1576 Linear Technology, LT1576 Datasheet - Page 5

• Manufacturer Part Number: LT1576
• Description: 1.5A/ 200kHz Step-Down Switching Regulator
• Manufacturer: Linear Technology

TYPICAL PERFORMANCE CHARACTERISTICS
Kool M is a registered trademark of Magnetics, Inc.
1.50
1.25
1.00
0.75
0.50
0.25
100
240
220
200
180
160
75
50
25
0
0
–50
0
0
Switching Frequency
Maximum Load Current
at V
Shutdown Supply Current
V
OUT
–25
OUT
= 5V
JUNCTION TEMPERATURE ( C)
5
0.1
SHUTDOWN VOLTAGE (V)
= 5V
0
INPUT VOLTAGE (V)
10
V
25
IN
0.2
= 25V
50
15
V
L = 60 H
L = 30 H
L = 15 H
IN
75
= 10V
0.3
W
20
100
1576 G16
1576 G10
1576 G13
U
125
25
0.4
1.50
1.25
1.00
0.75
0.50
0.25
1600
1400
1200
1000
800
600
400
200
0
0
0
–50
Maximum Load Current
at V
7
6
5
Error Amplifier Transconductance
V
OUT
1
Minimum Input Voltage
at V
OUT
V
–25
OUT
= 3.3V
5
OUT
JUNCTION TEMPERATURE ( C)
= 3.3V
= 5V
RUNNING VOLTAGE
INPUT VOLTAGE (V)
= 5V
0
STARTING VOLTAGE
LOAD CURRENT (mA)
MINIMUM
10
L = 60 H
10
MINIMUM
25
15
50
100
75
L = 30 H
L = 15 H
20
100
1576 G17
1576 G11
1576 G14
25
125
1000
0.001
0.01
1.0
0.1
0
Inductor Core Loss
1.50
1.25
1.00
0.75
0.50
0.25
250
200
150
100
CORE LOSS IS
INDEPENDENT OF LOAD
CURRENT UNTIL LOAD CURRENT FALLS
LOW ENOUGH FOR CIRCUIT TO GO INTO
DISCONTINUOUS MODE
50
V
0
OUT
0
0
0
Frequency Foldback
Maximum Load Current
at V
= 5V, V
V
5
LT1576/LT1576-5
OUT
OUT
INDUCTANCE ( H)
= 10V
5
IN
0.5
= 10V
= 10V, I
10
FEEDBACK VOLTAGE (V)
INPUT VOLTAGE (V)
10
OUT
TYPE 52
POWDERED IRON
Kool M
PERMALLOY
SWITCHING FREQUENCY
FEEDBACK PIN CURRENT
15
= 125
1.0
= 1A
15
®
20
L = 60 H
L = 30 H
L = 15 H
1.5
1576 G18
20
25
1576 G12
1576 G15
20
12
8
4
2
1.2
0.8
0.4
0.2
0.12
0.08
0.04
0.02
5
2.0
25