LM2576 Series
Test Circuit and Layout Guidelines
As in any switching regulator, layout is very important. Rapidly switching currents associated with wiring inductance generate voltage
transients which can cause problems. For minimal inductance and ground loops, the length of the leads indicated by heavy lines should
be kept as short as possible.
Single-point grounding (as indicated) or ground plane construction should be used for best results. When using the Adjustable version,
physically locate the programming resistors near the regulator, to keep the sensitive feedback wiring short.
Fixed Output Voltage Versions
+V
IN
1
V
IN
UNREGULATED
DC INPUT
(Figure 2a)
LM2576HV-
FIXED OUTPUT
D
3
5
FEEDBACK
4
OUTPUT
2
L1
100
H
D1
MBR360
V
OUT
+
1
GN00
F
ON/OFF
+
C
OUT
1000
F
L
O
A
D
C
IN
— 100µF, 75V, Aluminum Electrolytic
C
OUT
—1000µF, 25V, Aluminum Electrolytic
D1 — Schottky, MBR360
L
1
— 100µH, Pulse Eng. PE-92108
R
1
— 2k, 0.1%
R
2
— 6.12k, 0.1%
Adjustable Output Voltage Version
+V
IN
1
7V -60V
UNREGULATED
DC INPUT
(Figure 2b)
V
OUT
5.00V
R2
L
O
A
D
LM2576HV-
ADJ
3
5
FEEDBACK
4
L1
OUTPUT
2
100
H
MBR360
C
OUT
+
100
C
IN
F
GND
ON/OFF
+
1000
F
R1
V
OUT
=
R
2
)
R
V
R
1
(
OUT
−
)
V
REF
1
V
REF
1
+
R
(
2
where V
REF
= 1.23V, R1 between 1k and 5k
REV No:01-060813
TIGER ELECTRONICS CO.,LTD
8
TGS [ Tiger Electronic Co.,Ltd ]
