1
www.semtech.com
LM2575 & LM2576
1A & 3A Miniconverter
Switching Regulators
POWER MANAGEMENT
Revision 1, January 2001
u
Pin for pin replacement for Nationals LM2575/6
series
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DC-to-DC buck or buck/boost converter requiring
only 4 support components
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Fixed or adjustable voltages
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Preset output voltages of 3.3V, 5V and 12V
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Wide output voltage range, 1.23V to 35V
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82% typical efficiency @ 5V out
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Wide input voltage range, 4V to 40V
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Inhibit/enable control pin
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Industrial temperature range
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TO-220 and TO-263 packages
The LM2575/6 series switching regulators are monolithic
integrated circuits designed for use in buck or buck/
boost regulator applications requiring accurate output
voltages over combined variations of line, load and
temperature. This unique series greatly simplifies
switching power supply design. The LM2575 has a
maximum output current of 1A and the LM2576 is rated
for 3A.
The LM2575/6 series miniconverters include a
switching regulator and compensation network all within
the same package. Just add a choke, catch diode and
two capacitors to obtain an efficient DC-to-DC converter.
The current limit and thermal shutdown features of the
LM2575/6 series fully protect the device against
overstress conditions.
The LM2575/6 series offers an alternative to popular 3
terminal linear regulators by providing higher efficiency
with reduced heatsink size. In many applications a heat
sink will not be required.
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Micro controller power supplies
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Medical equipment
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Industrial power supplies
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Instrumentation power supplies
Description
Features
Applications
Typical Application Circuits
5
7
5
2
M
L
6
7
5
2
M
L
L
1
H
0
3
3
H
0
0
1
D
1
A
3
A
7
C
N
I
F
8
6
F
0
2
1
C
T
U
O
F
0
3
3
F
0
0
0
,
1
4
2001 Semtech Corp.
www.semtech.com
LM2575 & LM2576
POWER MANAGEMENT
Notes:
(1) Output sourcing current, resistive load, no inductor or capacitor.
(2) Feedback = V
O
+ 1.0V.
(3) Feedback = 0V.
Electrical Characteristics (Cont.)
r
e
t
e
m
a
r
a
P
l
o
b
m
y
S
s
n
o
it
i
d
n
o
C
t
s
e
T
n
i
M
p
y
T
x
a
M
s
ti
n
U
t
n
e
rr
u
C
e
g
a
k
a
e
L
t
u
p
t
u
O
)
2
(
V
0
=
t
u
p
t
u
O
I
L
V
N
I
V
=
N
I
d
e
t
a
R
2
A
m
V
1
-
=
t
u
p
t
u
O
5
.
7
0
3
t
n
e
rr
u
C
t
n
e
c
s
e
i
u
Q
)
2
(
I
Q
5
0
1
A
m
2
1
t
n
e
rr
u
C
t
n
e
c
s
e
i
u
Q
y
b
d
n
a
t
S
I
Y
B
T
S
0
5
A
)
V
5
=
n
i
P
ff
O
/
n
O
(
0
0
5
l
e
v
e
L
t
u
p
n
I
c
i
g
o
L
n
i
P
ff
O
/
n
O
V
H
I
2
.
2
4
.
1
V
4
.
2
V
L
I
2
.
1
0
.
1
V
8
.
0
t
n
e
rr
u
C
t
u
p
n
I
n
i
P
ff
O
/
n
O
I
H
I
V
F
F
O
/
N
O
)f
f
O
(
V
5
=
2
1
0
3
A
I
L
I
V
F
F
O
/
N
O
)
n
O
(
V
0
=
0
0
1
Unless otherwise specified: V
IN
= 12V for 3.3V, 5V and ADJ options and 25V for 12V option; V
OUT
= 5V for ADJ option; T
A
= 25C; V
IN
rated = 40V;
I
O
= 0.5 to 3A (LM2576), 0.2 to 1A (LM2575). Values in bold apply over full operating temperature range.
5
2001 Semtech Corp.
www.semtech.com
LM2575 & LM2576
POWER MANAGEMENT
TO-220-5
TO-263-5
e
c
i
v
e
D
)
1
(
e
g
a
k
c
a
P
t
n
e
r
r
u
C
X
X
-
T
5
7
5
2
M
L
5
-
0
2
2
-
O
T
)
3
()
2
(
A
1
R
T
.
X
X
-
S
5
7
5
2
M
L
5
-
3
6
2
-
O
T
)
4
(
X
X
-
T
6
7
5
2
M
L
5
-
0
2
2
-
O
T
)
3
()
2
(
A
3
R
T
.
X
X
-
S
6
7
5
2
M
L
5
-
3
6
2
-
O
T
)
4
(
Notes:
(1) -XX = Voltage Option. Available voltages are 3.3V
(-3.3), 5V (-5.0), 12V (-12), and ADJ (-ADJ), which is
adjustable between 1.23V and 35V.
(2) Lead bend options for TO-220-5 are: T-XX = Straight
in-line; T-XX-V = Vertical Staggered; T-XX-H = Horizontal
Staggered. Please refer to outline drawings at the end of
this datasheet.
(3) Only available in tube packaging. A tube contains 50
devices.
(4) Only available in tape and reel packaging. A reel
contains 800 devices.
6
7
5
2
M
L
,
5
7
5
2
M
L
n
i
P
n
o
it
c
n
u
F
1
V
N
I
2
T
U
P
T
U
O
3
N
O
M
M
O
C
4
K
C
A
B
D
E
E
F
5
F
F
O
/
N
O
N
O
M
M
O
C
s
i
B
A
T
Pin Configurations
Ordering Information
Block Diagram
PDF 
ZIP
