TABLE 1. LM2771 Performance with Different

Capacitor Configurations (Note 14)

CAPACITOR

CONFIGURATION

(V

TYPICAL

INPUT

RIPPLE

TYPICAL

OUTPUT

RIPPLE

C

C

C

45mV

8mV

C

C

C

94mV

19mV

C

C

C

105mV

11mV

C

C

C

102mV

16mV

C

C

C

120mV

15mV

Note 14: Refer to the text in the Recommended Capacitor Configurations

section for detailed information on the data in this table

Layout Guidelines

Proper board layout will help to ensure optimal performance

of the LM2771 circuit. The following guidelines are recom-

mended:

•

Place capacitors as close to the LM2771 as possible, and

preferably on the same side of the board as the IC.

•

Use short, wide traces to connect the external capacitors

to the LM2771 to minimize trace resistance and induc-

tance.

•

Use a low resistance connection between ground and the

GND pin of the LM2771. Using wide traces and/or mul-

tiple vias to connect GND to a ground plane on the board

is most advantageous.

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