LT3479EDE Ver la hoja de datos (PDF) - Linear Technology

Número de pieza

componentes Descripción

Fabricante

LT3479EDE

3A, Full Featured DC/DC Converter with Soft-Start and Inrush Current Protection

Linear Technology 

LT3479

APPLICATIONS INFORMATION

MINIMIZE THE AREA

OF THIS TRACE

TO VOUT

D

COUT

L1

CC

TO VS

TO VIN

CS

SW

GND

SW

GND

CSS

RC

L

SS

VS

LT3479

VC

VIN

FBN

RT

FBP

R1

CIN

RT

SHDN

VREF

TO GND

R2

TO SHDN

Figure 4. Suggested Board Layout

3479 F04

PLACE VIAS AROUND EXPOSED PAD

TO ENHANCE THERMAL PERFORMANCE

IL

2A/DIV

VOUT

5V/DIV

0.2MS/DIV

3479 F05

Figure 5. Start-Up with No Soft-Start Capacitor

IL

2A/DIV

VOUT

5V/DIV

0.2ms/DIV

3479 F06

Figure 6. Start-Up with CSS = 22nF

10

Switching Frequency

The switching frequency of the LT3479 is set by an exter-

nal resistor attached to the RT pin. Do not leave this pin

open. A resistor must always be connected for proper

operation. See Table 4 and Figure 7 for resistor values

and corresponding frequencies.

Table 4. Switching Frequency

SWITCHING FREQUENCY (MHz)

3.5

3

2.5

2

1.5

1

0.5

0.2

RT (kΩ)

1.78

2.87

4.32

6.49

10.2

17.8

39.2

113

3479fc

Share Link: