7

GM7130

3A STEP DOWN VOLTAGE SWITCHING

REGULATORS

Test Circuit and Layout Guidelines

Careful layout is important with any switching regulators. Rapidly switching currents associated with

wiring inductance generate voltage transients which can cause problems. To minimize inductance

and ground loops, the lengths of the leads indicated by heavy lines in Figure 1&2 below should be

kept as short as possible. Single point grounding (as indicated or ground plane construction should

be used for best results. W hen using the Adjustable version, place the programming resistors as

close as possible to GM2576, to keep the sensitive feedback wiring short.

Figure 1 Fixed Ouput Votlage Versions

D1 = Schottky

L1 = 100

μH

Figure 2 Adjustable Ouput Votlage Versions

D1 = Schottky

L1 = 100

μH

Unregulatedd

DC Input

100μF

68

0μF

L1

10

0μH

D1

L

O

A

D

4

Feedback

2

Output

3

GND

1

GM7130-x.x

5

ON/OFF

Unregulatedd

DC Input

100μF

68

0μF

L1

10

0μH

D1

L

O

A

D

4

FB

2

3

GND

1

GM7130-ADJ

R2

R1

5

ON/OFF